Abstract: A method of producing a filter unit, such as an air/oil separator, having a tubular filter element bonded at one end to an end cap, is proposed. The method includes the steps of: providing a tubular filter element and an end cap; melting a portion of the end cap; and embedding an end of the filter element into the melted portion of the end cap. The melted portion, on cooling, solidifies to bond the tubular filter element to the end cap. The end cap can be formed of thermoplastic containing an electrically conductive filler. The end cap can be formed of a thermoplastic having a melting point of at least 180 C. The method may further include, after the embedding step, a step of forcing melted thermoplastic from the melted portion radially against a side wall of the tubular filter element.

Abstract: A particle capture unit adopted to be exposed to a space in which particles fly includes at least a first layer formed of a plurality of first fiber-like materials and a second layer formed of a plurality of second fiber-like materials. The first fiber-like materials are thinner than the second fiber-like materials and arrangement density of the first fiber-like materials in the first layer is higher than that of the second fiber-like materials in the second layer, the second layer is interposed between the first layer and the space, and the first and second layers are hardened and bonded together by sintering.

Abstract: A method of manufacturing two screens in a jig by laying a length of woven wire cloth across two rectangular frames laid side by side in the jig with longer edges abutting, and orientating the cloth so that the warp wires extend continuously across the two screens. The cloth is tensioned and bonded to the frames after which it is severed along the join and surplus cloth is trimmed away from the edges of the frame. If the cloth has a square mesh and the warp wires are of greater cross-section than the weft wires, the warp wires will extend across the width of the frame, and if the cloth has a rectangular mesh, the greater number of warp wires per unit length also extends across the width of the frame. In each case warp wires will resist the stresses across the width of the central region of each opening.

Abstract: In one aspect a apparatus is provided that in one embodiment may include a permeable member made by combining a particulate additive to one or more materials, which materials when processed without the particulate additive form a substantially impermeable mass, wherein the permeable member inhibits flow of solid particles above a particular size through the permeable member.

Abstract: A cylindrical wound wire filter with an inner bore, suitable for use with an airbag inflator, has at least two different outer diameters and/or at least two different inner diameters. Wires in adjacent layers can be bonded together by adhesive or brazing, or have a sheet-like material therebetween, such as a ceramic filter paper.

Abstract: The present invention relates to a disc-shaped filter element and to a method to provide a disc-shaped filter element. A disc-shaped filter element has a diameter K, and comprises a first and a second ring-like shaped, liquid permeable support member having an outer edge having a diameter Ds and an inner central edge, having a largest width Ws. The disc-shaped filter element comprises a first and a second ring shape-like filter membrane, the first filter membrane being in contact with the first surface of the first support member, the second filter membrane being in contact with the first surface of the second support member. The outer edges of the first filter membrane, the second filter membrane, the first support member and the second support member are liquid tight fixed to each other. The disc-shaped filter element further comprises a hub having a central void space, an outer wall, at least one channel extending from this void space to this outer wall and a coupling means.

Abstract: A compressed wire mesh filter for an airbag assembly has one or more wires wrapped around the outer perimeter of the filter prior to final compression of the mesh to increase the hoop strength of the filter.

Abstract: Various embodiments of MEMS flow modules that both filter and regulate pressure are disclosed. One such MEMS flow module (58) has a tuning element (78) and a lower plate (70). A plurality of springs or spring-like structures (82) interconnect the tuning element (78) with the lower plate (70) in a manner that allows the tuning element (78) to move either toward or away from the lower plate (70), depending upon the pressure being exerted on the tuning element (78) by a flow through a lower flow port (74) on the lower plate (70). The tuning element (78) is disposed over this lower flow port (74) to induce a flow through the MEMS flow module (58) along a non-linear (geometrically) flow path. Preferably, a relatively small change in the pressure exerted by this flow on the tuning element (78) produces greater than a linear change in the flow rate out of the MEMS flow module (58).

Abstract: A separator tank assembly including a separator tank having an interior chamber, a corrosion-resistant layer applied over at least a portion of the separator tank interior chamber, and a separator element positioned within the interior chamber of the tank. The separator element is electrically connected to a portion of the separator tank beneath the corrosion-resistant layer.

Abstract: A filter assembly employs inward and outward radially displaced portions of a peripheral shoulder on the cartridge as components of a cartridge compatibility matrix. Alternative base assemblies include mounting structures complementary to the configuration of the peripheral shoulder to exclude incompatible cartridges. The peripheral shoulder is preferably a roll seam connecting first and second sections of the filter housing. The invention further contemplates a pattern of radial protrusions from a portion of the cartridge housing received in a base receptacle as part of a cartridge compatibility matrix. The base receptacle is configured to receive only those cartridges having a compatible pattern of radial protrusions.

Abstract: In order to achieve the object of providing a module having improved mechanical characteristics as well as a wide range of application, it is proposed that the module include at least one layer having open porosity, having an outer side facing a medium flowing into the module and an inner side facing away from the inflowing medium, manufactured from a material that can be sintered, selected from a group including metals, metal oxides, metal compounds, and/or metal alloys.

Abstract: The present invention provides a coolant for an air bag inflator in which unevenness in density in the axial direction is reduced even though the coolant is compressed in its axial direction. The coolant is a molded product made of wire rods and compressed in its axial direction. An absolute value of a difference between a radial pressure loss of the axially upper half portion of the coolant and a radial pressure loss of the axially lower half portion of the coolant is 10 mm H2O or less at a flow rate of 250 liters/minute under the atmosphere of 20° C.

Abstract: An apparatus for placing an end cap on a cylindrical workpiece includes a stationary support base, a guide member, a push bar, and an applicator device. The guide member is affixed to the stationary support base, and includes a ramp, disposed at an angle to the horizontal. The push bar is slidably movable in relation to the support base. The applicator includes a back plate which is operatively pivotally attached to the push bar at a pivot connection. The lower part of the applicator has a post attached thereto, which rides along the ramp of the guide member. Linear inward movement of the push bar, from a first position to a second position thereof, moves the applicator post up the ramp of the guide member, pivoting the applicator around the pivot connection, and causing the back plate to move from a substantially horizontal orientation to a substantially vertical orientation thereof.

Abstract: A method of manufacturing a mechanical basket (P) of substantially cylindrical shape for centripetal or centrifugal flow relative to an axis (R) and having rings (A) lying in planes perpendicular to the axis of revolution and wires (F) rigidly connected to the rings at regular intervals for the purpose of sieving a material is characterized in that assembling a wire (F) to a ring (A) is accomplished by a first operation of putting the wire (F) into position in a corresponding notch (EN) in the ring, and a second operation in which the wire is welded to the ring by melting a shoulder (EP1) of the ring, without adding any filler metal. In the method, a mechanical basket is made that presents better mechanical characteristics so that its lifetime is increased, and its cost of manufacture is reduced compared with conventional mechanical baskets.

Abstract: A modular base for a filter assembly includes a header portion defining a cavity for receiving a filter cartridge and a communication module defining fluid pathways to and from the base. Brackets extend from the header portion and include slots. Yokes extend from the communication module to complement the slots. The brackets and received yokes together define pathways into which generally tubular compression limiters are inserted. The compression limiters serve dual functions by retaining the communication module to the header portion and reinforcing the brackets. A sealing grommet disposed between the header portion and communication module enhances the sealed integrity of the base.

Abstract: A fuel filter having a formulation of a stable intermetallic compound of materials such as tin and antimony. The filter may have an integral porous structure or may be in the form of particles. It removes trace metal ions such as Ca and Na ions.

Abstract: The present invention provides a filter cartridge or filter unit (11) produced by a thermoplastic overmolding process that allows for using a single mold for overmolding a variety of different sized filter elements (12) or membranes and a method for sealing or hermetically sealing Said filter element (12) in said filter unit (11) or cartridge. The proposed method produces a more robust filter unit (11) or cartridge than those provided by the prior art.

Abstract: A screening screen assembly for a vibratory screening machine including an apertured plate, and a subassembly of an undulating support screen and fine screening screen and finer screening screen bonded to each other by a fused plastic grid and bonded to the apertured plate. A method of fabricating a screening screen assembly for a vibratory screening machine including the steps of providing a support screen, superimposing a plastic grid onto the support screen, superimposing a finer screening screen onto the fine screening screen, applying heat and pressure to the superimposed screens to fuse the plastic grid and thereby form a flat bonded laminate subassembly by causing the fused plastic grid to permeate the fine screen and the finer screen and the support screen, forming the bonded laminate subassembly into an undulating shape, providing an apertured plate, and bonding the undulating bonded subassembly to the apertured plate.

Abstract: A filter tube for use in earth coated type filters includes a flexible permeable tubular sheet internally supported by a helical spring. The internal spring is connected between opposite ends of the filter tube to support the full length of the tube wall. One end of the tube is connected to an external spring and anchor plate. In a slack position, the tube end folds over an end collar connected to the spring. Extension of the anchor plate applies tension to stretch the spring and tube to a taut position during a cycling operation which oscillates the tube to dislodge accumulated material.

Abstract: A screening screen assembly for a vibratory screening machine including an apertured plate, and a subassembly of an undulating support screen and fine screening screen and finer screening screen bonded to each other by a fused plastic grid and bonded to the apertured plate. A method of fabricating a screening screen assembly for a vibratory screening machine including the steps of providing a support screen, superimposing a plastic grid onto the support screen, superimposing a finer screening screen onto the fine screening screen, applying heat and pressure to the superimposed screens to fuse the plastic grid and thereby form a flat bonded laminate subassembly by causing the fused plastic grid to permeate the fine screen and the finer screen and the support screen, forming the bonded laminate subassembly into an undulating shape, providing an apertured plate, and bonding the undulating bonded subassembly to the apertured plate.

Abstract: Process for manufacturing a sifting device (or strainer baskets) for use in, e.g., in the paper industry for sorting and/or filtering fiber pulp suspensions. Sorter slits may be created between a plurality of substantially parallel rods inserted into respective insets formed in a support element. The rods may be securely held in place by first inserting the rods into the insets and then by permanently bonding the placement of the rods in the support elements with a bonding agent, e.g., as hard-soldering or brazing.

Abstract: An improved, spin-on, bead-lock filter which is particularly adapted for use as a high-pressure oil filter in a diesel engine is provided which comprises a housing containing a filter medium and having an inwardly deformed periphery, and a cover assembly including a cover plate and a retainer plate having mutually spaced apart outer edges for forming a recess that receives the inwardly deformed portion of the housing. A gasket is seated in the recess so that both a mechanical connection and a seal is formed between the cover assembly and the housing when the periphery of the housing is inwardly deformed pursuant to a bead rolling step in conformance with the assembly method of the invention.

Abstract: A screen basket for filtering an aqueous fiber suspension includes a cylindrical foraminous filter element, anchoring collars surrounding and fixed to opposite ends of the filter element, at least two support rings surrounding the filter element, and support rods for adjusting the support rings between axially contracted positions disengaged from the anchoring collars, and axially expanded positions engaging the anchoring collars and axially tensioning the filter element. In a first embodiment, the anchoring collars are relatively flexible. This allows the anchoring collars to be deformed for insertion of the cylindrical foraminous filter element within the support rings. Alternatively, the upper and lower support rings are divided into segments that are easily disassembled and reassembled to facilitate removal of a defective cylindrical foraminous filter element and installation of a new filter element.

Abstract: A progressive gap sand control screen comprising a plurality of parallel ribs spaced around an axis and a screen wire wrapped around the plurality of ribs having turns which extend along the length of the plurality of ribs such that adjacent turns have gaps therebetween, the gaps forming a gap profile in which the gaps near the upper end of the sand control screen are narrower than the gaps near the lower end of the sand control screen, the width of the gaps near the upper end of the sand control screen being less than the diameter of the particles which cause erosion, the gap profile includes a variable gap section near the upper end of the sand control screen and a constant gap section below the variable gap section, the variable gap section having a linear profile, a step type profile, or a nonlinear profile.

Abstract: A screening screen assembly for a vibratory screening machine including an apertured plate or frame, and a bonded subassembly of an undulating support screen and fine screening screen and finer screening screen bonded to each other by a fused plastic grid and bonded to the apertured plate or frame. A method of fabricating a screening screen assembly for a vibratory screening machine including the steps of providing a support screen, superimposing a plastic grid onto the support screen, superimposing a finer screening screen onto the fine screening screen, applying heat and pressure to the superimposed screens to fuse the plastic grid and thereby form a flat bonded laminate subassembly by causing the fused plastic grid to permeate the fine screen and the finer screen and the support screen, forming the bonded laminate subassembly into an undulating shape, providing an apertured plate or frame, and bonding the undulating bonded subassembly to the apertured plate or frame.

Abstract: A method of manufacture of a radial-flow filter particularly suitable for use as an input filter in a subterranean fluid (oil, gas, water) well starts with a length L of multi-perforate pipe, which may be an integral part of the production tubing of the well. The pipe is mounted in an engine lathe with the perforated length L between the headstock and the tailstock of the lathe. With the pipe rotating, a strip of metal wool, preferably stainless steel wool, is wrapped around the pipe in repeated, overlapping helical layers each aligned at an acute angle X to the pipe axis, with adjacent layers angularly displaced by an angle 2X. The completed filter may have a tubular wire mesh around the pipe, between the pipe and the innermost layer of steel wool, and a multi-perforate sheath over the outermost layer of wool.

Abstract: A method for manufacturing a supporting plate provided inside of a disc-type filter having filter media at surface portions thereof including the steps of: forming an annular plate having opposed surfaces; andforming a plurality of wave portions on the annular plate that alternately extend beyond the opposed surfaces in opposite directions by pressing, each of the plurality of wave portions extending substantially in a circumferential direction of the annular plate and the plurality of wave portions being arranged substantially adjacent to each other in a radial direction of the annular plate.The supporting plate has high pressure resistance, low-pressure loss property, good directivity of polymer flow and excellent polymer mixing effect, and it is suitable for use as retainer disposed inside of a filter.

Abstract: A method of manufacture of a long radial-flow filter particularly suitable for use as an input filter in a subterranean fluid (oil, gas, water) well starts with a length of multi-perforate pipe, which may be an integral part of the well 's production tubing. The pipe is mounted in an engine lathe with the perforated length between the headstock and the tailstock of the lathe. With the pipe rotating, a strip of metal (steel) wool is wrapped around the pipe in repeated, overlapping helical layers each aligned at an acute angle X to the pipe axis, with adjacent layers angularly displaced by 2X. The completed filter has a tubular wire mesh around the pipe, between the pipe and the innermost layer of steel wool, and a multi-perforate sheath over the outermost layer of wool.

Abstract: An improved method for fabricating a filter for use in automotive air bag inflators which comprises forming a hollow cylindrical inner core or combustion screen of filter material and outer filter layers wound outward from the surface of the core so as to be maintained in cylindrical relation thereabout. This invention is specifically directed to an improved filter which does not include a perforated support tube and relies on only the interior combustion screen for support in the final wrapping of the remaining filter structure.

Abstract: A generally planar expanded metal filter media support structure is provided. The filter media support structure includes a first row of perforations mutually separated, one from another, by a perforation distance along a first axis parallel to the plane of the support structure and at least a second row of perforations parallel to the first row of perforations offset from the first row of perforations along the first axis by a first offset distance greater than zero and less than one-half the perforation distance and offset along a second orthogonal axis in the plane of the support structure by a second offset distance.

Abstract: A multi-layer composite screen having filters of a plurality of layers superposed one upon another is provided. Each filter of the plurality of layers has wires of a substantially triangular or trapezoidal cross section arranged in parallel to one another with a continuous slit of a substantially V-shaped cross section being formed between respective adjacent wires, said slit widening increasingly inwardly from the surface of the screen. The wires of one filter of the respective adjacent filters cross the wires of the other filter and the respective adjacent filters are fixed to each other at crossing points of the wires of the respective filters. In one aspect of the invention, the wires are formed with linear projections extending in the longitudinal direction of the wires which facilitate electrical welding of the filters of the adjacent layers.

Abstract: A fluid filter assembly having a body with a chamber for receiving a filter element supported by the body. At least one cleaning device is positioned adjacent the inlet side of the filter element. The cleaning device includes a hollow duct for collecting dislodged particulate matter, an adjustable scraper and a deflector substantially equal in length to the scraper. Nozzles may be provided for directing pressurized cleaning fluid toward the cleaning device.

Abstract: A screening screen assembly for a vibratory screening machine including an apertured plate, and a bonded subassembly of an undulating support screen and fine screening screen and finer screening screen bonded to each other by a fused plastic grid and bonded to the apertured plate. A method of fabricating a screening screen assembly for a vibratory screening machine including the steps of providing a support screen, superimposing a plastic grid onto the support screen, superimposing a finer screening screen onto the fine screening screen, applying heat and pressure to the superimposed screens to fuse the plastic grid and thereby form a flat bonded laminate subassembly by causing the fused plastic grid to permeate the fine screen and the finer screen and the support screen, forming the bonded laminate subassembly into an undulating shape, providing an apertured plate, and bonding the undulating bonded subassembly to the apertured plate.

Abstract: A method for making a screen includes preparing a plurality of elongated supporting plates, each of which being formed with a plurality of transversely and spacedly arranged grooves, and arranging the elongated supporting plates spacedly in a parallel manner to align the grooves on one of the elongated supporting plates with the grooves on an adjacent one of the elongated supporting plates; preparing a plurality of elongated bars, each of which being formed integrally with a longitudinal constricted portion, the longitudinal constricted portion normally having a transverse width wider than that of the grooves; heating the elongated supporting plates to expand the grooves; inserting the longitudinal constricted portion of each of the elongated bars into expanded grooves in order to juxtapose parallel the elongated bars and to form slots therebetween; and cooling the elongated supporting plates in order to permit contraction of the elongated supporting plates and the grooves so as to hold tightly the elongated

Abstract: A caul screen is made with metal cable having a low twist level of between 1 and 5 turns per inch and where the cable is made with filaments that have been coated with brass; the cable is woven into a mesh to form the screen.

Abstract: A method for sealing a porous membrane constructed, at least in part, of a PTFE based material to a support gasket constructed, at least in part, of a PTFE based material. The method includes providing such a PTFE porous membrane of a preselected shape and size and providing such a PTFE support gasket of a preselected shape and size. The method further includes positioning the membrane and the support gasket in a predetermined appositional relationship within a press. The press includes a press tool of a predetermined configuration and size. The method then includes sealing the membrane and support gasket together at a common seal-zone by pressing the press tool against the membrane and the support gasket with the pressing means at a predetermined pressure for a predetermined dwell to form the membrane/gasket assembly. The method lastly includes removing the membrane/gasket from the pressing means.

Abstract: A method of installing a filter belt onto each of a pair of wind up rollers disposed on either side of a filter housing is disclosed. The filter belt is detachably secured at either end to a respective roller by a sewn in flexible element received in an undercut groove in the roller surface. Each end of the belt is fully inserted lengthwise into the undercut groove in the respective roller surface while bending the flexible element around side plates of the filter housing so as to secure each end of the filter belt to a respective roller.

Abstract: A reusable multilayer filter for use with a beverage brewing apparatus. The multilayer filter includes a foraminous support player, a porous mesh layer and a multiplicity of wrinkles formed in the porous mesh layer. The foraminous support layer has a multiplicity of spaced apart holes extending through the layer. The porous mesh layer overlies and is attached to the foraminous support layer. The mesh layer is formed of a woven, etched, or deposited material which has a multiplicity of small openings extending therethrough. The openings in the porous mesh layer are smaller than the holes in the foraminous support layer for selectively retaining material having a dimension larger than the openings. The wrinkles in the porous mesh layer are formed in spaced apart areas which are defined by a perimeter of the holes in the foraminous support layer. The wrinkles increase the effective surface area of the filter.

Abstract: A method for and a device to insert filters into disposable pipette tips uses a turntable adapted to receive a plurality of tips adjacent its circumference and powered by a stepping motor to incrementally rotate pipette tips to various positions for appropriate actions. After a tip is placed in the turntable, it is moved successively to a position where a filter of predetermined size may be inserted into the tip. The filter is then tamped into the desired final position at still another position. After checking for the presence of a filter, the pipette is removed from the turntable.

Abstract: An electrostatic air cleaner collector and/or ionizer section has their oppositely charged elements being formed of single, continuous, electrically conductive elements, spirally wound around insulator rods to jointly define a spiral passage through which air is caused to flow. The collector and ionizer may be assembled separately by such a winding process, or they may contain common insulator rods around which the conductive element of both sections may be simultaneously wound. A conductive rod may be inserted to electrically interconnect the high voltage elements of the respective ionizer and collector sections.

Abstract: A prepack well screen assembly has a resistance welded outer screen concentrically mounted in radially spaced relation on a perforated mandrel, thereby defining an annulus in which a sintered metal prepack sleeve is loaded. The longitudinal spacing distance between adjacent turns of the outer screen selectively exclude sand fines of a predetermined minimum size. The porosity of the sintered metal prepack sleeve is selected to pass sand fines in the size range of from about 20 microns to about 150 microns. The effective inlet flow area through the sintered metal prepack sleeve is substantially greater than the effective inlet flow area through the outer screen. The sintered metal prepack screen excludes sand fines from inflowing formation fluid during the initial production phase following a gravel pack operation, without limiting production of formation fluid.

Abstract: A method of assembling an inflator for a vehicle occupant restraint is disclosed. The inflator comprises a housing that provides a gas flow path, a filter that includes a plurality of successive filter layers extending across the flow path, and a seal that is disposed between the housing and the filler. The method comprises the step of assembling the seal and filter by embedding a part of the filter into the material of the seal to provide a sealing relationship between the seal and filter. Thereafter, the preassembled filter and seal is positioned in the housing.

Abstract: A filter element for filter systems, which comprises a plurality of plate members having a number of apertures therethrough and cutout grooves formed in the surface thereof, a plurality of wire members each having a retaining leg portion, which is inserted into one of the grooves of the plate member, whereby the top surfaces of the wire members are flashed in a definite plane for forming a plurality of slits for filtering a liquid.

Abstract: A cell-type filter cartridge is disclosed having netting thereon, as well as a method for producing same. Briefly stated, the surface area of filter material exposed to unfiltered fluid has disposed thereon a netting thereby preventing flaking, cracking and the like of filter media during backflow or cleaning operations. The netting is secured to the cell by a molded circumferential retainer and a circumferential centrally disposed ring.

Abstract: A filter cartridge for treating a fluid passing therethrough includes a filtering medium and a support container for holding the filtering medium. The support container includes a solid side wall having first and second ends and a pair of perforated end walls, one located on each end of the side wall. A pair of connectors is provided for securing a respective one of the end walls to a respective end of the side wall. A sleeve secures the connectors to the side wall in a substantially leak-proof manner.

Abstract: An automatic transmission fluid filter is disclosed, comprised of a metal base member, a plastic cover member attached to the base member, enclosing a volume. Filtration material inside the volume is interposed between an inlet and outlet to the filter. A plastic overmold around the periphery of the union of the metal and plastic members hermetically seals the filter except at the inlet and outlet. In a preferred embodiment, the metal base member includes a flanged edge which is secured to a flanged edge of the cover member by the overmold. Slots through the flange of the base member allow plastic of the overmold to flow through, connecting together plastic on both sides of the flange. Also, the base member flange ends curled lip embedded in the plastic of the overmold. Edge sections of the filtration material extend to and between the union of the base and cover members over some sections of the edge of the filter.

Abstract: A double cylinder screen comprises an inner reinforcing cylinder which performs a pressure-resisting function against an external pressure and an outer screen cylinder which performs a screen function. The inner reinforcing screen comprises inner rods disposed cylindrically at a predetermined interval in the axial direction of the screen and a spiral reinforcing member wound on the outside of the inner rods and welded to the inner rods. The outer screen cylinder comprises screen rods disposed at a predetermined interval in the axial direction on the outer periphery of the inner reinforcing member and a wire wound spirally about the outside of the screen rods and welded to the screen rods. The width of a slit of the reinforcing member is larger than the width of a slit of the wire. The double screen cylinder is improved in its stength and can be manufactured without requiring a costly jig.

Abstract: A hollow fiber separatory module for separating fluids includes an annular hollow fiber separatory bundle encased in a pressure resistant shell. A region of the bundle is constricted so that the walls of the fiber are densified. Consequently, compaction of these fibers during operation is reduced. The constricted region is encapsulated by a potting material. Minimization of compaction aids in maintaining a sealing contact between the fibers and the potting material. "O" rings extending from the pressure resistant shell may seal the space between the pressure shell and the fiber bundle. The constricted portion may accommodate the "O" rings so that a pressure resistant shell of uniform outside diameter can be used. The fiber bundle may be constricted by heating, chemical treatment, applying pressure or application of tension during winding.

Abstract: A method and apparatus are disclosed for providing a crimp seal pleated filter assembly having a two piece housing with a filter media disposed within the housing and having a plurality of alternating pleats. The apparatus includes a first and second jig for supporting the housing halves and an odd number of at least three or more movable pleat forming blades on one side of the apparatus. The odd number of blades are movable through one of the supporting jigs with blade edges opposing the other supporting jig. The odd number of blades includes an independently movable center blade and a first pair of outer blades with opposing surfaces of adjacent blades defining a first plurality of pleat forming spaces. An even number of pleat forming blades are positioned with blade edges opposing the first plurality of pleat forming spaces and are spaced apart from and in alignment with the opposing pleat forming blades.