Abstract: A fluid filter includes a first batting of high loft, non-woven, fibrous fluid-permeable material with a plurality of openings formed through the thickness thereof across the length and width of the batting. A second layer of high loft, non-woven, fluid-permeable fibrous batting is attached to the first layer and extends across the entire length and width of the first layer. Preferably, the first and second layers are adhered together to form a single integral fluid filter. In the preferred form of the invention, the openings in the first batting have side walls which are perpendicular to the upper surface of the batting, such that fluid flow impacts on the upper surface of the batting, rather than directly impacting on the side walls.

Abstract: An apparatus for removing particles from a fluid stream includes an unobstructed channel for conveying a stream in turbulent flow and a series of objects extending at least along one side of the channel, the objects being closely spaced from each other in the direction of flow so as to define therebetween spaces in which eddies penetrate from the channel to cause collection of particles on surfaces of the objects upon decay of the eddies.

Abstract: A product wherein a layered web of melt blown fibrous filter media is produced by a unitary die including several die sources with facing layers of the fibrous filter media being attenuated by opposed fluid streams at preselected included angles and with the fiber layers being free from bonding together and with the fibers in each layer being minimally bonded.

Abstract: A filter composite comprising a first layer of glass fibers having random orientation, the layer being porous to gas flow therethrough; a porous mat of sufficient stiffness as to support the glass fiber layer during use as a filter, the mat consisting of compacted glass fibers, and; an additional porous layer carried by the mat to block escape of glass fibers or particles from the filter composite during gas flow therethrough. The first layer fibers have diameters between about 0.000035 and 0.00015 inch.

Abstract: Disclosed is an adsorbent fibrous nonwoven structure composed of (1) a matrix of pulp fibers having a first exterior surface and a second exterior surface; and (2) an adsorbent material integrated into the pulp fiber matrix so that the concentration of adsorbent material adjacent the first exterior surface of the nonwoven structure is at least about 60 percent, as determined by optical image analysis, and the concentration of adsorbent material adjacent the second exterior surface is less than about 40 percent, as determined by optical image analysis. This adsorbent nonwoven structure provides useful strength and low-lint characteristics. The fibrous nonwoven structure of the present invention may be laminated together or to surfaces of other materials.

Abstract: A filter composite comprising a first layer of glass fibers having random orientation, the layer being porous to gas flow therethrough; a porous mat of sufficient stiffness as to support the glass fiber layer during use as a filter, the mat consisting of compacted glass fibers, and; an additional porous layer carried by the mat to block escape of glass fibers or particles from the filter composite during gas flow therethrough.

Abstract: A meltblown web is composed of fibers having a narrow fiber size distribution (expressed as % coefficient of variation of the average fiber diameter) and low packing density. The web is characterized as a soft lofty web and exhibits exceptional filtration capability. The web preferably comprises fibers having an average fiber size of between 3 and 10 microns and a packing density of between 5 to 15%, and a CV of 15 to 40%.

Abstract: An efficient, highly porous fabric filter medium capable of filtering air at temperatures up to about 500.degree. F. (260.degree. C.) has been provided. The filter medium is made from a polyimide fiber and is especially well suited for use in combination with a rotating drum filtering machine, thereby providing high temperature air filtration at a lower initial equipment and installation cost, and with subsequent lower operating and maintenance costs than have been previously possible.

Abstract: A sheet filter made up of a flat textile article carrying micrometric particles of a resistant and/or adsorptive additive, the textile article made up of fibers which upon heating become temporarily adhesive without fusing. Advantageously the textile article is a nonwoven fibrous fleece or a pile fabric; if a fleece, a second fleece can be placed over the additive particles so heating unites the fleeces as well as adhereing the particles.

Abstract: A recirculating fiber filter (1) and method is provided for removing particulates from moving fluid streams. High aspect ratio fibers (2) are used which readily nest with each other to form the high voidage fiber filter bed. In the method, fibers are continuously removed from the bottom of the bed regenerated to remove particulates and recycled back to the top of the bed and distributed thereon. Dirty fluid is passed from the top to the bottom of the filter. Dendrites of the particulate impurity appear to buildup in a thin section (A) at the top of the filter and provide the primary mechanism for further particulate entrapment. Recirculation of fibers offers a continuously fresh volume of fibers at the top for capture of particulates.

Abstract: Laminated composite structures for use in making fluid filters are disclosed. Such structures comprise (a) a densified high loft layer of powder bonded nonwoven fabric, rebulkable by heating, laminated to (b) a filter media or element that supplies stiffness to the laminate. Also disclosed are methods of making fluid filters, e.g., ones used to filter inlet air for internal combustion engines, from such laminates, and fluid filters containing such laminates in which the nonwoven layer has been rebulked by heating.

Abstract: A filter element is formed by spirally winding at least two layers of filter material about a central, perforate supporting core. The layers include a relatively fine porous filter material and a relatively coarse porous filter material. The layers may be formed from blankets of material, or one or both layers may be pleated. The fine filter material extends beyond the edge of the coarse filter material to overlie and close the longitudinal ends of the layers of the coarse material. Fluid to be filtered passes radially through the element until it encounters a clogged or plugged area. The fluid will then take a circumferential spiral route until it again finds an open area of the filter and can pass radially toward the core.

Abstract: Provided is a strong, flexible filter element comprising a wet laid non-woven element of glass fibers, synthetic short fibers, and polymer fibrids having a softening point below the softening point of the short fibers. In the filter element, the glass fibers are bound to the synthetic short fibers, e.g., aromatic polyamide short fibers such as poly(m-phenylene isophthalamide) short fibers, by the polymer fibrids, e.g., cellulose acetate fibrids, which act as a binder. The filter element exhibits excellent chemical resistance and a usefulness in removing particulates from gases at temperatures below 400.degree. F.

Abstract: Filtering material and filtration apparatus employing the filtering material. The filtering material includes a perforated laminate of a plastic sheeting and a metalized coating adhesively attached to a fabric backing. A filter bag formed from this filtering material is mounted within a support structure so that the metalized coating is electrically connected to the support structure.

Abstract: A fabric filter bag, a method of making such a bag, and apparatus using such bags, in which the bag is a tube of yarn knit into stitches defining a ground and stitches defining terry loop pile extending from the ground. In accordance with the present invention, such a fabric filter bag, method of making a bag, and apparatus using a bag is improved by the inclusion of a conductive strand for conducting electrostatic charges otherwise accumulating on the fabric filter bag away from the bag so as to suppress accumulation or build-up of such charges.

Abstract: An internal loading cylindrical air filter apparatus having a circular tubular knit pile fabric filter element extending unsupported between end plates to provide an essentially full length unobstructed filter area, and having a rotating internal suction cleaning nozzle therefor. The tubular filter element is supported at its entry end by a detachable angle ring having a cylindrical ring flange extending through an opening in the entry end plate of the apparatus to permit endwise assembly and disassembly of the fabric filter element into the apparatus. Annular or helical strands may extend in circumferential engagement with the filter element for restraining it from ballooning out of effective cleaning distance with respect to the rotating suction nozzle under heavy filtering conditions, and a crank may be provided for adjusting the extending length of a helically extending restraining strand for controlling the degree of restaint imposed on the filter element.