Abstract: An air filter unit of the HEPA type having a filter core of zig-zag folded media enclosed by a four-sided frame having two side casings and two end casings. Each end casing includes a recess extending into the inwardly facing surface thereof and bounded on all four sides by marginal edge portions of the end casing. The end flaps of the folded media are adhesively secured to the inwardly facing surfaces of the side casings and the recesses in the end casings are filled with an adhesive initially in a flowable state and hardenable to a solid state. The zig-zag edges of the folded media are disposed entirely within the adhesive, as are tenons extending from the ends of the side casings, thereby forming a mortise type joint between the side and end casings. A plurality of channels, preferably of dove tail cross section, extend across and communicate with the recesses in the end casings.

Abstract: A filter arrangement is suggested where the filter means (38) is placed between distance pieces (48, 50, 52). In order that the longitudinal edges (64, 66, 68) of the preferably zigzag-folded distance pieces cannot cause any damage to the filter means, they are provided with a substantially edgeless cap (90, 92, 94), of which the maximum width equals that of the distance pieces.

Abstract: An axial oil filter including at least one pair of axially aligned filter elements includes an elongate filter body and a removable filter cartridge. The filter elements are mounted on an axial conduit which is a part of the filter cartridge, and the filter cartridge placed in the filter body so as to define upper and lower chambers, and a bypass flow path between the upper and lower chambers. Fluid to be filtered may flow into either of the chambers and will flow upward through the lower filter element and downward through the upper filter element. The filtered fluid is collected from a passage defined by a screen between the two filter elements, and passes outward from the filter through the outlet port.

Abstract: A filter cartridge having an improved end cap and tube support design is taught. Briefly stated, an outer cage has circumferentially disposed thereround a plurality of truncated triangular shaped saw tooth-like projections each of which as a rounded nub or projection at the outermost truncated end. An inner cage similarly has a plurality of alternating projections coextensive therewith, with the thickness of the furthermost portion of the projection being tapered towards the bottom where the projection meets the end of the inner cage. The inner cage is disposed within the outer cage and placed between end caps having circumferential regions adapted to receive the projections disposed at the end of the outer and inner cage respectively. A filtration medium is disposed between the inner and outer cage.

Abstract: Disposable filter element, adapted for use in a high-pressure filter housing, has a plurality of layers of flexible filtering material, some layers being formed with openings through which a portion of the fluid can flow without being filtered, and at least one downstream layer of the filtering material being free from such openings. When all of the layers of filtering material have the same pore size, the total area of the openings in each layer is larger than that of the openings of any downstream layer. Each opening-containing layer of the filtering material removes part of the contaminant in the fluid. Interposed between adjacent opening-containing filtering layers is a layer of flexible transport material, and there is a layer of flexible prefiltering material positioned upstream of said filtering layers.

Abstract: A tubular filter element for liquid filters comprises a perforated support pipe. Disposed around the inside of the support pipe is a tubular filter layer which comprises a folded sheet of filter material. Within each end of the filter element a spring washer is disposed for biasing the end of the tubular filter layer outwardly against the inside of the support pipe. In this pre-biased state, the ends of the filter element are joined to disks by means of a hardenable casting material.

Abstract: New, high surface area per unit volume, generally cylindrical filter cartridge for gaseous or liquid filter applications are described. These filter cartridges which comprise a nested arrangement of substantially disk shaped layers having a radial pleat pattern embossed therein, are capable of achieving higher surface areas per unit volume than can be achieved with conventionally pleated filter cartridges. Utilization of the filter media is extremely high as blocking of adjacent layers of filter media is avoided and fluids are evenly distributed over the total area of the filter media as a result of the series of channels created by the nesting of the disk shaped pleated layers.

Abstract: An air driven filtration system is disclosed. The system includes a power module housing, an air driven motor and a removable filter pack. The power module is adapted to receive an intake adapter for connecting a remote filter pack thereto which may be placed in a contaminated work area. The remote filter pack is connected to the power module by flexible ducting.

Abstract: HEPA or pre-HEPA filter media are made by forming a web of melt-blown polypropylene fibers. The melt-blown process is accomplished at a low through-put of about 1 pound per inch of die width per hour and at a high fluid flow rate of about 250 to 325 standard cubic feet per minute. The resulting web has fibers with an average diameter of about 5 microns and surface pores of less than 30 microns in size. By cold calendering the web with pressure of between 100 and 300 psi, further filter efficiency can be achieved. The resulting calendered web has surface pore sizes less than 20 microns.

Abstract: A filter unit (1) has an annular pleated paper filter element (9) the pleats of which are sealed at their end edges (92) to define inwardly opening pockets. Consequently, gaskets (8) need only seal the radially innermost periphery of each end of the filter element (9), and end plates (4,5) supporting the gaskets (8) may be given a smaller diameter than the element (9).

Abstract: A dust collector of a large capacity suitable for cleaning air or gases and for separating out by-products of an industrial process for further utilization. The collector generally comprises a continuous and integral filter medium which is suspended form a plurality of downwardly extending frames forming a series of separate elements having a triangular cross-section, each element being relatively wide at the top and narrow at the bottom to define, between adjacent elements, a divergent collecting space which is wide at the bottom.

Abstract: A plurality of air filtration units located within an enclosed contaminated space have their exhaust connected to an air box located within the enclosed space. The interior of the air box is in communication with an area outside of the enclosed contaminated space. An isolation chamber is mounted on one wall of the air box to permit the insertion of air sampling cassettes into the interior of the air box so that the exhaust air in the air box may be monitored. The isolation chamber also permits the selective removal of the air sampling cassettes from the air box. In both the insertion and removal operations, the isolation chamber prevents contaminants from being released into the enclosed space.

Abstract: A gas purification apparatus which is operable utilizing an upflow direct impingement coalescer. A central inlet in the lower portion of a column expands the flow of air and liquid droplets (vertical flow to horizontal separation). The droplets lose velocity and are impinged in the packing. Migration is first outward from the main gas flow and then downward. Finally, the liquids are drained at the bottom. A collar around the central inlet insures that liquid will not reenter into the central inlet.

Abstract: This invention relates to a pleated high efficiency particulate air filter and separators therefor in which the separators for filter media to be wound therearound comprise a lattice with tapered struts or spacers, a rounded pleat fold contacting member, and vertically spaced apart air inlet and outlet media supporting flat members to provide uniform internal support for the pleats. The struts are formed to provide a tapered space between filter media and the struts after the media is wound around the separators.

Abstract: A gas filter which is formed from a single continuous sheet of material folded along a plurality of parallel fold lines and interconnected at appropriate folds so as to produce an element having spaced front and rear faces and a plurality of partition walls extending between said front and rear faces and defining therebetween a plurality of chambers of wedge-shaped cross-section, the wedge-shapes of adjacent chambers being oppositely orientated, and, said sheet being formed with apertures such that gas can flow through the filter from the front face to the rear face and in so doing is constrained to pass through apertures in at least one partition wall so as to pass through at least two adjacent chambers.

Abstract: Filter and method for filtering bacteria-laden saliva droplets and aerosols from human breath particularly suitable for use in pulmonary function testing where a low pressure drop is required. A relative large pore filter medium is oriented at a large angle relative to the overall flow through the filter such that both larger droplets and smaller aerosols impact and are retained on the filter medium.

Abstract: An air filter of the accordion-pleated type with successive media pleats providing substantially parallel walls held in spaced relation by corrugated spaces and sealed within a square or rectangular frame. The spacers which separate the media in the upstream direction are of higher amplitude than the spacers separating the media walls on the downstream side. The upstream spacers are preferably about 2 to 21/2 times greater in amplitude than the downstream spacers. The filters are particularly advantageous in applications where the loading or dust collection rate is accelerated and the final pressure drop is uncommonly high. Dust holding capacity is significantly increased over similar, prior art filters having equal spacing of the media walls in the upstream and downstream directors.

Abstract: A filter system for a hot cell comprises a housing adapted for input of air or other gas to be filtered, flow of the air through a filter element, and exit of filtered air. The housing is tapered at the top to make it easy to insert a filter cartridge using an overhead crane. The filter cartridge holds the filter element while the air or other gas is passed through the filter element. Captive bolts in trunnion nuts are readily operated by electromechanical manipulators operating power wrenches to secure and release the filter cartridge. The filter cartridge is adapted to make it easy to change a filter element by using a master-slave manipulator at a shielded window station.

Abstract: A selective fluid flow control device has a control element which is held in sealing relationship with a housing, with first and second seals being formed to confine the fluid flow through the control element. The first and second seals define a sealed chamber from which the fluid is excluded, and a gas conduit communicates between outside of the housing and the sealed chamber for applying a test pressure to the chamber to test the quality of these seals. In a preferred embodiment, the selective fluid control device is a filter arrangement for a clean room or the like, and the seals are formed against the filter gasket by a seating arrangement formed of an extruded rail that has a web and first and second ribs, the ribs being biased against the gasket.

Abstract: A satellite pre-filter cabinet positions replaceable air filters in an area in which air polluting harmful industrial dusts, including friable asbestos and/or fumes and gases are present and must be removed. The satellite air filter cabinet is connected to negative air pressure devices and filters remotely situated as for example outside of the polluted area.

Abstract: A filter element has a generally ring-like structure which basically comprises a plurality of generally radial sections circumferentially arranged to define a central space. Each radial section has a plurality of circumferentially zigzag pleats formed from a ribbon of a filtering sheet material. The radial sections are circumferentially connected such that radially inwardly open generally radial spaces and radially outwardly open generally radial spaces are defined. The radially inwardly open radial spaces are closed at the axially opposite ends by end walls. Fluid to be filtrated can enter the radially outwardly open radial spaces and then passes through the zigzag pleats into the radially inwardly open radial spaces and thus into the central space. The ring-like structure has many modifications.

Abstract: The filter element of the present has a plurality of wavy portions which are so arranged that a plurality of wavy portions make a generally ring like structure. In order to reduce the pressure drop when the fluid flows through the filter element, the present filter element has a special shaped radial gaps. Namely, the width of a first radial gaps, which is formed within adjacent wavy portions and which connects with an inner space formed at the center of the generally ring like structure, increases from the outer end thereof to the inner end thereof. The width of a second radial gap, which is connected with outer atmosphere, decreases from the outer end thereof to the inner end thereof. Both axial ends of the wavy portions are covered with the adhesive sheet on which adhesive layer is cladded.

Abstract: A pleated filter element comprising a sheet of filter material disposed in generally cylindrical configuration and having a series of longitudinally extending pleats. The pleats have outer radial extremities that lie on an outer circle and inner radial extremities that lie on an inner circle. The end pleats in the series terminate in side edges which are disposed in contiguous relation. A mass or bar of synthetic resin connects and encapsulates the side edges, and the connected end pleats have the same radial depth as the remaining pleats in the filter.

Abstract: A filter cartridge of the type made from a sheet of filter paper pleated as an accordion on a cylindrical surface. It is produced by pinching pairs of contiguous pleats at various levels in order to make on the outer surface of the cartridge a plurality of honeycombs. The invention results in substantially prolonged life of the filter cartridges, which have applications in a variety of uses, including regeneration of solvents of washing baths for dry cleaning machines, filtration of air for internal combustion engines and water filtration.

Abstract: A portable environmental clean air frame facility including a power unit section and a clean air section. The frame is formed by P.V.C. pipes and fittings so that clear plastic sheeting material may be formed and draped over the clean air section to form a clean air enclosure. The power unit section includes a blower motor having a prefilter unit on each end. One end draws air from the surrounding medium and one is connected to the clean air enclosure. The prefiltered air is directed through a HEPA filter, through an air delivery duct and into the enclosure. A bypass damper is provided for controlling the air flow velocity and for producing either a positive or negative pressue in the enclosure.

Abstract: A filter device comprising a cannister container of impervious material having therewithin a pleated filter with at least one of the side edges of each of the individual pleats being sealed. Appropriate inlet/outlet structure is provided with the cannister body, as well as an appropriate support base for holding same. In one embodiment, the pleated filter material has both side edges of the individual pleats sealed and large spaced flow passageways between the respective edges are provided by a plurality of seals between the edges. Another embodiment has only one side edge of the individual pleats sealed with the other side edge being open for collectively sealing same by the structure of the cannister body itself. In this embodiment, a larger plurality of fluid flow passageways are provided by multiple sealed portions between the respective side edges of the individual pleats.

Abstract: A filter pack for gas and/or liquid filtration employing filter medium surfaces disposed between pairs of spacers, with the spacers having a corrugated configuration and the edges of the corrugations of each spacer preferably being mutually parallel to one another, the improvement wherein the edges of the corrugations of the spacers placed adjacent to the two sides of one filter medium surface are locally oriented at an angle toward one another.

Abstract: A specially arranged, five stage, four compartment, vacuum loader is provided to collect, remove, and dispose asbestos and other hazardous material in an efficient, effective, and safe manner without exposing surrounding personnel to the collected asbestos or other hazardous material.

Abstract: An air purification system for use with an air conditioning apparatus which includes an air circulation system having supply air flow to a given area and return air flow for drawing air from that area. The air purification system includes an inlet and an outlet. A conduit communicates the inlet with the air circulation system for drawing therefrom a portion of the air passing therethrough. A conduit communicates the outlet with the air circulation system downstream of the inlet for returning the portion of the air back to the circulation system after it has passed through the air purification unit. A superheating conduit also communicates between the inlet and an exhaust of the air conditioning apparatus, such as the chimney of a furnace.

Abstract: This invention relates to a pleated high efficiency particulate air filter and separators therefor in which the separators comprise a lattice with flat or rounded spacers, a rounded pleat fold contacting member, and vertically spaced apart air inlet and outlet media supporting flat members to provide uniform internal support for the pleats, and to eliminate sharp edges and corners which would tend to injure the media under compression.The separators may be formed of plastic by molding into a single unit or into multiple segments which may be joined side by side to provide a desired separator length. The structure permits enclosure and bonding of the assembled pleats and separators with the end portions of each encased by a bonding material.

Abstract: A room air treatment system includes a housing or cabinet defining a filter chamber and a blower chamber. A blower, disposed within the blower chamber, is connected to the filter chamber by a duct. Positioned within the filter chamber is a HEPA filter and activated carbon or charcoal filter assembly. The housing defines an air inlet covered by a prefilter and an air outlet within which a louver assembly is disposed. A pivotal bail or generally U-shaped rod engages a generally rectangular filter retaining frame to sealingly retain the filter stack within the filter chamber. A control system is included for controlling operation of the blower motor.

Abstract: An air filter assembly (1) includes an outer casing (6) having end, rear and downstream portions which are generally planular and thus easily settable on the floor during installation, with the downstream portion being mountable flush to a furnace (3) or the like. An inner filter-holding drawer (7) is provided for easy insertion and removal from the open front casing portion. At least one end wall (10, 11) of the casing is provided with a springable latch (34) adjacent the casing front opening and which snappingly engages and holds a cover (9)in place when the drawer is within the casing. The drawer end walls (44, 45) include external grooves (52) which slide over rails (56) correspondingly mounted internally of the casing side walls. The tolerances are such that the grooves are wider than the rails.

Abstract: A clean room is adapted to provide a plurality of clean air zones with different degrees of cleanliness. Air is passed through high efficiency particulate air filters in the ceiling of the room and withdrawn through shutters in the floor of the room. The shutters are adjustable to maintain a pressure-balanced system. The room is divided by walls and partitions to define different zones which are filtered by different classes of filters depending on the degree of cleanliness required in each zone.

Abstract: An air filter for a motor-driven tool such as a portable motor-driven chain saw includes a prefilter through which aspirated air flows into a chamber partly defined by a cover that can be secured to the housing of the motor-driven tool. From this space, the air flows through a main air filter to the carburetor of the motor. The main air filter and the prefilter are configured as a one-piece double filter unit.

Abstract: A particulate filter medium is formed of a sintered composite of 0.5 micron diameter quartz fibers and 2 micron diameter stainless steel fibers. A preferred composition is about 40 vol. % quartz and about 60 vol. % stainless steel fibers. The media is sintered at about 1100.degree. C. to bond the stainless steel fibers into a cage network which holds the quartz fibers. High filter efficiency and low flow resistance are provided by the smaller quartz fibers. High strength is provided by the stainless steel fibers. The resulting media has a high efficiency and low pressure drop similar to the standard HEPA media, with tensile strength at least four times greater, and a maximum operating temperature of about 550.degree. C. The invention also includes methods to form the composite media and a HEPA filter utilizing the composite media. The filter media can be used to filter particles in both liquids and gases.

Abstract: A high efficiency particulate air filter, and a method of fabricating the same, are disclosed, with the filter being characterized by being lightweight and readily disposable after use. Further, the filter may be fabricated in a basic or universal form, which permits it to be utilized to form any one of a number of possible specific mounting configurations by the placement of one or more specifically designed headers about the outer periphery. The filter comprises a sheet of HEPA filtering media folded upon itself in accordion fashion to form a filter pack, and a relatively thin and lightweight peripheral frame surrounding and supporting the pack. The frame is composed of a relatively hard, crust-like, air impermeable molded material which is self-bonded and sealed to the filter pack to effectively preclude the leakage of air therebetween.

Abstract: The present invention provides a filter element made wholly of fluorocarbon resin, including as essential elements a filter material produced by folding a sandwich-form sheet comprising a filter membrane made of a fluorocarbon resin and net supporters made of a thermoplastic fluorocarbon resin superimposed on the both surfaces thereof into a pleat form and liquid-tightly welding the edge parts of the both sides of the pleated sheet, sealed end parts produced by embedding the both end parts of said filter material except the central openings into a thermoplastic fluorocarbon resin to force the resin into the pleats, whereby the both end parts are each integrally and tightly welded, and fluorocarbon resin caps welded liquid-tightly with said sealed end parts, and production thereof.

Abstract: A filter element suitable for use in a filter device such as air cleaner, oil filter or fuel filter for an automobile is disclosed. It includes a pair of end plates and a filter paper which is disposed between the end plates and folded so as to form rectangular-shaped sections, thus folded filter paper forming a hollow cylinder. The cylinder is divided into a plurality of portion areas by virtual planes extending in the radial direction thereof, and the rectangular-shaped sections in each of the portion areas are arranged such that every other sections are maintained in a parallel relation with predetermined spaces therebetween.

Abstract: A filter element has a generally ring-like structure which basically comprises a plurality of generally radial sections circumferentially arranged to define a central space. Each radial section has a plurality of circumferentially zigzag pleats formed from a ribbon of a filtering sheet material. The radial sections are circumferentially connected such that radially inwardly open generally radial spaces and radially outwardly open generally radial spaces are defined. The radially inwardly open radial spaces are closed at the axially opposite ends by end walls. Fluid to be filtrated can enter the radially outwardly open radial spaces and then passes through the zigzag pleats into the radially inwardly open radial spaces and thus into the central space. The ring-like structure has many modifications.

Abstract: An air filter comprising a first layer of reticulated foam plastic material having a thickness of between 10 mm and 20 mm and a porosity of between 5 and 60 pores to the linear inch, a second layer of reticulated foam plastic material having a thickness of between 6 mm and 10 mm and a porosity of between 60 and 100 pores to the linear inch, and at the interface between said first and second layers an open mesh substrate approximately one millimeter in thickness constricting a maximum of about ten percent of each of the first and second layers, the filter being impregnated with a flame proof retention and plasticizer additive, the first and second layers being bonded together at the interface.

Abstract: An air cleaning apparatus comprises a housing that includes four housing parts and a motor unit with an axial fan arranged in the middle zone of the apparatus. The motor unit forms with upper and lower housing parts a single unit. The air is sucked by the motor through a circular air channel. The outer zone of the air channel is surrounded by a multi-layer filter mat in the form of a shell. Along the side surface of the apparatus, air inlet openings are arranged. In the central zone on the upper surface of the cover air outlet openings are provided.

Abstract: An automatic assembly machine for assembling a pleated filter material and a perforate hollow core member includes a wrapping station, an adhesive application station and a clamping station. A conveyor moves the filter material and the core member together as a unit through the wrapping station and the adhesive application station. The clamping station both clamps the seam to which adhesive has been applied for a period of time sufficient to permit curing of the adhesive joint, and simultaneously conveys the filter material and core member assembly. A method for assembling a pleated filter material and a perforate hollow core member includes the steps of conveying both the filter material and the hollow core member to a point where they come in mutual contact, supporting one of the members on the other, and simultaneously conveying the filter material and core member sequentially through a wrapping station and an adhesive application station.

Abstract: Filter cartridge for filtering apparatuses for removing impurities from hot and/or highly pressurized flowing gases, with zig-zag formed, folded, gas-penetrated filter material whose part surfaces caused by the folding, between the fold lines, are arranged in relatively close juxtaposition to each other, wherein a preferably thin-walled plate 15 is arranged in the space between two respectively adjacent part surface 12, 13 of the filter material 11, with said plate having one straight-formed edge 16 lying in the inside of the fold 14 and one opposite lying zig-zag formed edge 17, and the bend or crest lines 18 between the two edges 16, 17 rise steadily towards the medial plane 19 of the plate 15.

Abstract: An improved fluid filter element and a filter medium therefor include a rigid core having a coupling member attached at each end for absorbing axial stress. A filter medium includes a plurality of pockets and first and second neck portions sealingly attached to said coupling member.

Abstract: A spacing and scoring tool for creating high density pleated filter media, and the media therefor is disclosed herein. A blade (14) having curvilinear portions (22, 22a) and linear portions (21, 21a) create an island pattern when scored into flat or corrugated media (16). The island are preferably located centrally upon the corrugation peaks (18) either at every peak or periodically. The resulting pattern when foled produces filter media with automatic pleat spacing and this structure can be used at very high pleat spacings beyond 10 pleats per inch. The blade (14) is solid on its contact face at the curvilinear portions for preventing island collapse when the media is folded.

Abstract: A high efficiency particulate air filter is disclosed which comprises a frame surrounding and sealably supporting the filter pack, with the frame composed of four separate side panels which are rigidly interconnected at their abutting ends by means of corner plates. The corner plates are in the form of two flanges disposed at right angles to each other, and the flanges are closely received within slots formed on the outer face of the side panels. The corner plates preferably extend across the entire width of the side panels of the frame to impart substantial rigidity to the frame, and a sealing material is disposed in a recess which extends along the bight of the corner plates to provide a continuous seal along the abutting ends of the side panels.

Abstract: A filtration module formed from a first flexible sheet having a first edge section, an opposed second edge section and an interior section, comprising engaging each portion of the first and second edge sections respectively to uncorrugated first upper and lower terminal elements. Corrugations are formed in the first upper and lower terminal elements of the first flexible sheet-terminal elements assembly, and slits are cut in the interior section of the first flexible sheet-terminal elements assembly, with the slits extending transversely to the edge sections. Each adjacent pair of slits in the interior section defines a ribbon element. One or more filtration modules may be assembled to form a filter by stacking the elements or by winding the filtration module or modules around a central core. The stacked or wound filtration modules are supported within a housing so that each ribbon element is disposed in a fully extended, fexible state.

Abstract: An improved corrugated sheet aluminum spacer for use in pleated media air filters is disclosed. The spacers are folded in zig zag fashion along one edge in a succession of V formations having a first height and width, and along the opposite edge in a succession of V formations having both heights and widths approximately one-fifth of the first height and width. Since the fold lines are substantially parallel, there are five V formations within a given width of the opposite edge for each one along the first edge, the fold lines of the intermediate V formations extending from the second edge only a portion of the distance to the first edge, but preferably about 90% of the length of the sheet. The V formations are formed by passing the aluminum between a pair of rolls with forming blades having overlapping edges which engage the sheet. The height or amplitude of the V formations at the small end is on the order of 0.03 to 0.04 inches in aluminum sheet having a thickness of 1 to 2 mils, preferably 0.0015 inches.

Abstract: A high-efficiency electrostatic air filter device having high dust collecting efficiency and a long service life is provided. The device is composed of a charging section for electrically charging the dust particles in a gas to be treated, and a dust collecting section provided with a filter medium meandering in the direction orthogonal to the direction of passage of the gas to be treated, a plurality of separator electrodes disposed in the spaces between every adjoining part of said meandering filter medium with or without the medium of insulating spacers from both upstream side and downstream side of said filter medium, and electroconductive elements provided for effectively supplying a high DC voltage between said separator electrodes.

Abstract: An improved fluid filter element and a filter medium therefor include a rigid core having a coupling member attached at each end for absorbing axial stress. A filter medium includes a plurality of pockets and first and second neck portions sealingly attached to said coupling member.