MXPA98003319A - Filter element and fabricac method - Google Patents

Abstract

The present invention relates to a coreless filter element, characterized in that it comprises: a substantially homogeneous mixture of a base fiber and a binder material compressed to form a first non-woven fabric strip of selected porosity; woven being wound spirally on itself in multiple lapped layers to form a first web having a selected radial thickness, a second nonwoven web comprising a substantially homogeneous blend of a base fiber and a binder fiber compressed to form a second web strip non-woven fabric of selected porosity that defers from the porosity of the first strip of fabric, the second strip of fabric being spirally wound on itself into multiple overlapping layers to form a second band having a selected radial thickness, the first and second bands being overlapped and joined to form a porous filter element autosop ortan

Description

FILTER ELEMENT AND MANUFACTURING METHOD TECHNICAL FIELD The present invention relates to filter elements and to the machines and methods used in their manufacture.

TECHNICAL BACKGROUND There are machines that are used to manufacture tubular filter elements in a continuous process. The patent of E.U.A. No. 4,101,423 discloses a tubular filter element made in a single-stage multiple winding machine of helically wound and overlapping layers such as an inner layer of a highly porous paper with high moisture resistance, a second layer of a material of microporous thin filtration of a sterilizing grade and an outer layer of a porous sheet of expanded polyethylene and a porous outer layer to support the filtration material. The layers are wrapped on a fixed mandrel to self-overlap in a single layer overlap and advance in unison along the mandrel while they are wrapped, such that there is no relative movement between the adjacent layers of the laminate. An adhesive material that blocks the passage of the particulate matter and the bacteria that are being filtered seals the second filtration layer in the rasping region. The ends of the tubular laminate structure are impregnated over a predetermined length adjacent to each edge of the structure with a suitable adhesive sealant material such as a wet vaporization compound of polyurethane. When the adhesive material is cured, the end portions provide mechanical support for the tube, while blocking the passage of fluid or contaminants in the form of particles and bacteria. (See column 5, Ins. 4-26). A circularly wound spiral chromatographic column is shown in U.S. Patent No. 4,986,909. Here, a sandwich or laminate of alternating layers of a sheet-shaped inflatable fibrous matrix and layers of separating means is compressed to have a fluid-proof configuration. Typically, the peripheral edges of the alternating disks of the inflatable fibrous matrix and the separating means are joined. Preferably, the fibrous matrix contains or has a thermoplastic polymeric material bonded thereto, as well as the separating means. The edges can be joined by suitable heating, eg, sonic welding (See Col. 10, Ins. 40-61). Another circular winding and spiral wound filter element is described in the U.S.A. No. 5,114,582, and comprises one or more filter elements wound spirally on a permeable and cylindrical transport tube. Each filter element comprises a heat sealed membrane element and a feed separator. (See summary).

A process for the manufacture of high permeability porous tubes made from a mixed carbon-carbon material on a mat strip spirally wound on a mandrel is described in US Pat. No. 5,264,162. The porous tubes are made of said material by winding on a mandrel a non-woven sheet, made of a carbon fiber precursor, followed by compression and heat stabilization of the assembly. The sheet is impregnated with a resin, followed by a thermal carbonization treatment of the resin. Pipes having a high permeability, small pore diameter and an interior surface of low roughness are obtained. (See summary). The use of successive sterilant layers is also described, making it possible to obtain, in the final tube, pore diameters that increase in the direction of the flow to be filtered, generally from the inside to the outside of the tube. It is advantageous that these pore diameters are substantially in a ratio of 10 between one layer and the next, which can be obtained by adjusting the density of the mat and / or the diameter of the fibers. (See Col. 4, Ins. 10-20). An element of the single wrap filter helically wound in the patent of US Pat. No. 5,409,515 is disclosed, which includes a porous membrane of a polytetrafluoroethylene and one or more sheets composed of fibers made of a synthetic thermal fusion resin. (See summary). The sheets are thermally fused over a selected length. (See Col. 4. Ins. 40-46).

DESCRIPTION OF THE INVENTION The general object of the invention is to provide an improved filter element made with improved methods and machines for its manufacture. This object is achieved with a filter element made of at least a homogeneous mixture of base fibers and a binder material which is compressed to form a non-woven fabric of selected porosity. The binder material has at least one surface with a melting temperature lower than that of the base fibers. The non-woven fabric is given a selected geometrical shape and heated to thermally melt the base fibers and binder material to create a porous filter element. The preferred form is a helically wound tube with several sheets, each sheet being self-overlapping and compressed to overlap another sheet. Each sheet is preferably heated and compressed individually and the sheets can be selected to have different porosities and densities. The binder material is selected from the group consisting of thermoplastic material and resin, and the base fibers are selected from the group consisting of thermoplastic and natural materials. The machinery preferably used to produce the filter element employs a manufacturing method which includes the step of forming a homogenous ribbon of a base fiber and a binder material, as explained above, which is compressed to form a non-woven sheet and that is further compressed to form a non-woven fabric of selected porosity. Several sheets of non-woven fabric are wound helically on a multi-station wrapping machine with individual bands, each activated by a winch to form individual layers that overlap to form a laminate. The tension of each band is selected to compress each layer to a selected degree. Each layer is heated to complete the thermal fusion step. Cooling fluid is pumped through the hollow mandrel to prevent excessive heat accumulation in the mandrel. The machine is controlled by a computer that receives input signals that adjust the functions of the machine, such as the speed of the drive motor of the winch, the tensions of the sheet wrapping bands, the temperature of the heating arrangement used for complete the thermal fusion of each layer and the flow of the cooling fluid flowing through the hollow material. The above objects as well as additional objects, features and advantages of the invention will become apparent in the following detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a perspective view in partial section of the preferred embodiment of the invention, illustrating a filter element without multi-overlapping center made in a four-stage wrapping machine using four rolls of selected non-woven fabric. Figure 2 is a cross-sectional view illustrating the filter element without multi-overlap center of Figure 1 being formed on a hollow mandrel. Figure 3 is a schematic top view of three machine stations used to manufacture the filter element of Figure 1. Figure 4 is a perspective view illustrating the preferred embodiment of a multi-stage winding machine used to produce the filter element of Figure 1. Figure 5 is a block diagram of the preferred nonwoven fabric manufacturing process that is used to produce the filter element of Figure 1. Figure 6 is a schematic diagram of a computer-based system used to control the winding machine of Figure 4. Figure 7 is a schematic diagram of a control system used to control the multi-stage winding machine of Figure 1.

BEST WAY TO CARRY OUT THE INVENTION With reference to figure 1 of the drawings, the number 11 designates a multi-lapped centerless filter element constructed in accordance with the principles of the invention. This includes a first multi-overlap nonwoven fabric strip 13, a second multi-overlap nonwoven fabric strip 15, a third multi-overlap nonwoven fabric strip 17 and a fourth multi-overlap nonwoven fabric strip 19. Each strip of fabric 13, 15, 17 and 19 is spirally or helically wound in overlapping layers to form overlapping bands 14, 16, 18, 20, respectively. The radially inner surface 21 of the band 14 forms the periphery of an annular axially extending space extending from one end 25 of the filter element to the opposite end 27 of the filter element 11. In the drawings the thickness of the film is exaggerated. cloth. In Figure 2 of the drawings, numeral 47 designates a hollow cylindrical mandrel with an annular outer surface 49 and an annular inner surface 51, said annular inner surface 51 forming the periphery of a cylindrical channel 53 through which a means of Liquid or gaseous heat exchange (not shown). The band 14 of the multi-overlapping nonwoven fabric strip 13 is shown overlapped by the strip 15 of multi-overlapping nonwoven fabric strip 15, which in turn is overlapped by the strip 18 of the non-woven fabric strip. multi-overlapped 17, which is then overlapped by the band 20 of the multilayer non-woven fabric strip 19. As shown in Figure 3 of the drawings, only three stages of the multistage winding machine shown are shown. in greater detail in Figure 4. In Figure 3, a first compression band 55 is shown wrapping, in a multi-lapped style, the non-woven fabric strip 13 around the hollow material 47. A second compression band 57 shows wrapping, in a multi-overlapping style, the non-woven fabric strip 15 around the multi-overlapping nonwoven fabric strip 13. A third compression band 59 is shown wrapping, in a multi-overlapping style, the strip non-woven fabric 17 around the strip of tea the non-woven multi-overlap 15. A first heating arrangement, preferably of infrared heaters 63, is shown in a position to apply heat, simultaneously with compression of the compression band 55, to the multi-overlapping nonwoven fabric strip 13. A second heating arrangement of infrared heaters.65 is shown in a position to apply heat, simultaneously with the compression of the compression band 57, to the multi-overlapping nonwoven fabric strip 15. A third heating arrangement of infrared heaters 67, is shown in a position to apply heat, simultaneously with compression of the compression band 59, to the multi-overlapping nonwoven fabric strip 17. Referring now to Figure 4 of the drawings, the number 71 designates a multi-stage winding machine for making filter elements without a multi-layered center 11. A roll of non-woven fabric strip 13 is designed stra is mounted on a roll holder 75 consisting of an erect member 77 on which are mounted, at selected locations, one or more cylindrical roll supporting arrows 79 extending perpendicularly outwardly from the erect member 77 to receive the center tubular (not shown) of the nonwoven fabric strip roll 13. The erect member 77 is connected at its base to a plurality of horizontal ends (not shown) that extend perpendicularly outwardly to such a length to provide support for the member. erect 77, each roll support arrow 79 and each roll of nonwoven fabric strip 13 loaded onto each roll support arrow 79. A feed tray 81 consists of a rectangular plate with its two opposite opposite ends 83 and 85 each turned upward at a right angle to form a channel 84 that supports and guides the strip of non-woven fabric 13. Each stage of the winding machine 71 has e a feed tray 81 and a tension roll 147 connected to an air cylinder (not shown). A heating arrangement support 87, a mounting plate for the first heating arrangement 63, is erected vertically in a plane that is perpendicular to the axis 89 of the hollow mandrel 47. The heating arrangement support 87 is connected along its base edge to a structure machine support 91 extending parallel to the axis 89 of the hollow mandrel 47 and supporting each stage of the multistage winding machine 71. The heating arrangement support 87 has an inlet surface (not shown) and a exit surface 93. The hollow mandrel 47 is connected to the exit surface 93 and extends through each stage of the multistage winding machine 71. Attached to the entrance surface of the heater mounting bracket 87 is a conduit (not shown) for transporting the heat exchange medium of a pump device (shown schematically in Figure 7, number 324) through an opening (not shown). a) in the heater support bracket 87 and in the cylindrical channel 53 of the hollow mandrel 47. Connected to the outlet surface 93 of the heater mounting bracket 87 is a plurality of heater actuators 97 each of which consists of a metering adjustment mechanism 99 connected through a meshing mechanism (not shown) to an actuator plate 101 of the heater. Attached to each heater actuator plate 101 and extending outward from the outlet surface 83 of the heater mounting bracket 87 and parallel to the shaft 89 of the hollow mandrel 47 is an infrared heater 63.

Each infrared heater 63 is attached to a corresponding heater actuator plate 101 so as to direct its heat perpendicular to and in the direction of the hollow mandrel 47. Each infrared heater 63 extends outwardly from the outlet surface 93 of the heater mounting bracket 87 at a selected distance. A pair of winches consisting of a driving winch 105 and a driving winch 106 stands vertically with its axes (not shown) perpendicular to the axis 89 of the hollow mandrel 47 and on each side thereof. The driving winch 105 is mounted on a gearbox 107 of the driving winch and the driving winch 106 is mounted on a winch gearbox 109. The drive winch gearbox 107 is connected at its base to a gearbox platform 113. The gearbox platform 113 is a rectangular plate that rests on the support structure 91 of the machine in a horizontal plane. A winch drive motor (shown schematically in Fig. 7, number 314) is mounted below the platform of the gearbox 113 and has an arrow (not shown) which is understood through an opening (not shown) in the gearbox platform 113 and connected to the gears of the gearbox 107 of the driving winch. The gearbox 107 of the driving winch is connected to the gearbox 109 of the driving winch by a wedge arrow (not shown in the first stage, but identical to the chopped arrow 111 of the fourth stage) thus providing a means for driving the winches 105 and 106 at the same angular velocity but in opposite directions. The gearbox 109 of the driving winch is connected at its base to a sliding plate 115 of the gearbox. The lower side of the sliding plate 115 of the gearbox has a plurality of grooves extending along its length and parallel to the length of the platform 113 of the gearbox. The slots in the sliding plate 115 of the gearbox receive the rails of a digital linear encoder 117 thereby allowing the digital linear encoder 117 to increasingly measure the location of the driving winch 109 along the rails of the digital linear encoder 117. in relation to a reference point in the digital linear encoder 117. The digital linear encoder 117 may be of the type described in U.S. Patent No. 4,586,760 or any other linear increment measuring device known to those skilled in the art. Near the center of the platform 113 of the gearbox and through the thickness of the platform is an arc-shaped notch (not shown in the first stage, but identical to the arc-shaped notch 119 of the fourth stage), whose rope is parallel to the length of the platform 113 of the gearbox. A set of adjustment screws of the gearbox platform (not shown in the first stage, but identical to the set of screws 121 of the platform of the gearbox of the fourth stage) passes through the notch in the form of an arc and is received inside a threaded opening (not shown) in the support structure 91 of the machine. The angle of the compression band 55 relative to the hollow mandrel 47 can be adjusted by loosening the set of set screws from the platform of the gearbox and manually moving the platform 113 of the gearbox relative to the support structure 91 of the machine. The capstan sleeves 123 and 125 are concentric about the axes of the driving winch 105 and the driving winch 106, respectively. The radially inner surfaces of the cap sleeves 123 and 125 coincide with the radially outer surfaces of the drive winch 105 and the drive winch 106, respectively, and joined thereto by suitable means in a selected location on the driving winch 105 and on the driving winch 106. The protrusions 127 and 129 of the annular winch sleeve extend radially outward of the driving winch 105 and the driving winch 106, respectively. The winch sleeves 123 and 125 with the projections 127 and 129 of the winch sleeve can be attached to the driving or driven winches at each stage of the multistage winding machine 71 to prevent the compression bands 57, 59 and 61 from slipping towards down on the driving or driven winches. The compression band 55 forms a closed loop around the half of the periphery of the driving winch 105 and the half of the periphery of the driving winch 106 and is placed in tension by the distance between the axes of the driving winch 105 and the driving winch 106. The compression band crosses on itself only once between the driving winch 105 and the driving winch 106. Furthermore, the compression band 55 forms a single spiral around the hollow mandrel 47. An air tensioning cylinder 133 is mounted on the platform 113 of the gearbox at the same end as the gearbox 109 of driven winch. The air tensioning cylinder 133 is a commonly used pneumatic cylinder with an arrow 135 extending from one end of the air tensioning cylinder 133 in parallel with the length of the platform 113 of the gearbox and connected at the opposite end of the the arrow 135 with the gearbox 109 of the driven winch. In Figure 4, 3 additional stages of the multistage winding machine 71 are shown. Each additional stage consists of components identical to those of the first stage except that the heater mounting bracket 137 of each additional stage includes a concentric opening 139 about the axis 89 of the hollow mandrel 47 through which the hollow mandrel 47 passes with enough space for the strips 14, 16, 18 and 20 of the coreless filter element 11 several times overlapped. The feeder tray 91 can be replaced by a feeder tensioner 141 consisting of a vertically erect member 143 connected at its base to a plurality of horizontal ends 145 and connected at the opposite end to the feed tensioning rollers 147. The strips are compressed. of non-woven fabric 13, 15, 17 and 19 between the feed tensioning rollers 147 for controlling the tension in the non-woven fabric strips 13, 15, 17 and 19 while entangling in the hollow mandrel 47 at each stage of the machine 71 multi-stage winding. Referring now to Figure 5 of the drawings, a block diagram of each step of the manufacturing process of the non-woven fabric strips 13, 15, 17 and 19 is illustrated. Each important step of the manufacturing process is described in separate block. In block 151, step 1 is the acquisition of base fibers and binder materials, usually in the form of a bullet acquired from a textile fiber producer. The non-woven fabric strips, 13, 15, 17 and 19 are composed of one or more base fibers and / or binder materials. If a strip of non-woven fabric 13, 15, 17 or 19 consists of only one base fiber, it must be of the type consisting of an external lower melting point protection and an inner core of higher melting point so that when heated sufficiently, the outer protection melts to form a binder material and the inner core remains intact to serve as the base fiber. If a strip 13, 15, 17 or 19 is composed of two or more base fibers, at least one of the base fibers must have a lower melting point than the others so that when heated sufficiently it melts to form the binder material; or be of the type of protection and center mentioned above so that when heated sufficiently the external protection melts to form the binder material and the inner core remains intact to assist the remaining base fibers. In block 153, step 2 is to open and weigh the base fibers and binder materials. The base fibers and the binder materials are transported to a synchrometer where they open more for the preparation of the final mixture in block 155. In block 155, step 3 is the final mixture of the base fibers and the binder materials by means of which the individual base fibers and the binder materials are thoroughly mixed by means of a series of beating cylindrical rollers to provide a homogenous dispersion of the base fibers and the binder materials. This step is performed in a mixer similar to the mixer described in U.S. Patent No. 3,744,092. In block 157, step 4 is the transport of the base fibers and binder materials thoroughly mixed from the mixer to the feeder through an air duct system consisting of a duct of approximately 30 centimeters in diameter, a through which the air circulates at a speed of approximately 522 meters per minute. In block 159, step 5 is feeding the base fibers and binder materials intermixed in a feeder similar to the feeder described in U.S. Patent Nos. 2,774,294 and 2,890,497. Block 161, step 6 is the formation of a strip in which the base fibers and binder materials are conveyed from the feeder to a strip former, similar to the strip former described in U.S. Patent Nos. 2,890,497 and 2,703,441 which consists of a plurality of cylindrical rollers and a counter-rotating beater to form a continuous strip of the base fibers and homogeneously dispersed binder materials. Block 163, step 7 is the liquefaction and compression of the strip carried out in a series of air stream furnaces and / or alternative heat sources in which a flow of air heated to a selected temperature is cooled in the band thus causing the liquefaction of all or part of the particle types of the base fibers and the homogeneously dispersed binder materials. Simultaneously to the liquefaction of all or part of the particular types of base fibers and homogeneously dispersed binder materials, there is the strip compression formed continuously into a thin nonwoven sheet. Liquid water is pumped through ducts in the air stream furnaces where it is poured into heated stainless steel plates creating low pressure steam. The air in the air stream ovens is almost 100% saturated with this low pressure steam. The level of saturation required depends on the temperature inside the airflow furnaces, which varies from 93 to 287 ° C. The low pressure steam neutralizes the static electricity created by the air that is recirculating at speeds of up to 18,877 cubic meters per minute. There is a pressure differential across the strip in the air stream oven between 10 and 20 centimeters of water column. The residence time for the strip in the air-flow ovens depends on the speed of discharge of the strip that is occurring in the strip former in step 6 and is coordinated with it. In block 165, step 8 is the compression of the thin non-woven sheet of base fibers and homogeneously dispersed binder material created in step 7 into a non-woven fabric of a selected thickness required for the desired efficient filtration, transporting the sheet thin nonwoven between two cylindrical stainless steel rollers. In block 166, step 8-A, there is the formation of a master roll of the non-woven fabric by winding the non-woven fabric created in step 8 around a master core in the conventional embobinator. In block 167, step 9 is to cut the non-woven fabric strip 13, 15, 17 and 19 of the non-woven fabric created in step 8-A. Cutting devices are placed at selected points across the width of the non-woven fabric to cut it longitudinally into a plurality of non-woven fabric strips 13, 15, 17 and 19. In block 169, step 10 is to wind the webs. non-woven strips 13, 15, 17 and 19 in tubular cores. This step is performed in a commonly used coiler, which consists of a plurality of cylindrical rolls for aligning and winding the non-woven fabric strips 13, 15, 17 and 19 in the cores. The complete manufacturing process of the non-woven sheet takes place in a controlled humidity environment. The relative humidity of the air in the environment varies from 60 to 80% as measured by the wet bulb / dry bulb thermometer and an enthalpy scheme. Referring now to Figure 6 of the drawings, a schematic diagram of the preferred computer-based processing data and the control system of the multi-stage winding machine 71 is illustrated. It should be understood that the winding machine 71 can be operated manually. The data processing system 200 is controlled primarily by computer readable instructions in the form of software such as written input through Intellution, Inc. of Norwood, Massachusetts. Said software is executed within the central processing unit (CPU) 250 to cause the data processing system 200 to control selected functions of the winding machine 71.

The CPU 250 retrieves, decodes and executes instructions, and transfers information to and from other resources via the main data transfer path of the computer, the main transmitting path 254 of the system. The main transmitting path 254 of the system connects the components of the data processing system 200 and defines the means for data exchange. The main transmitting path 254 of the system typically includes data lines for sending data, address lines for sending addresses and control lines for sending interrupts and for operating the main transmitting path 254 of the system. The memory devices coupled to the main transmitting pathway 254 of the system include the random access memory (RAM) 256, the read-only memory (ROM) 258 and the non-volatile memory 260. Said memories include circuitry that allows the information to be stored and recovered. The data stored in the RAM 256 can be read or changed by the CPU 250 or other hardware devices. ROM 258 contains stored data that can not be modified. Non-volatile memory is memory that does not lose data when the energy is removed from it. Non-volatile memories include ROM, EPROM, flash memory, bubble memory or CMOS RAM 260 backed by batteries. The CMOS RAM 260 supported by batteries can be used to store information about system configuration. Access to RAM 256, ROM 258 and non-volatile memory 260 can be controlled by memory controller 262 and controller 264 of the transmitting main path. The memory controller 262 can provide a translation function of the address that translates the virtual addresses into physical addresses as the instructions are executed. The memory controller 262 can also provide a memory protection function that isolates the processes within the system and isolates the system processes from the user's processes. Thus, a program that runs in user mode can only access the memory mapped by the virtual address space of its own process; can not access memory within the virtual address space of another process, unless the memory that is shared between the processes has been established. An expansion card or expansion board is a circuit board that includes chips and other electronic components connected in a circuit that adds functions or resources to the computer. Typical expansion cards add memory, 266 disk drive controllers, video support, parallel and serial ports, and internal modems. Thus, vacuum segments 268 may be used to receive various types of expansion cards. The disk controller 266 and the floppy controller 270 include integrated circuits for special purposes and associated circuitry that direct and control the reading of, and writing to, a hard disk drive 272 and a floppy disk or floppy disk 274, respectively. Said disk controllers handle functions such as the placement of the read / write head, mediating between the disk unit and the microprocessor, and controlling the transfer of information to and from the memory. An individual disk controller 266 may be capable of controlling more than one disk unit 272 and / or 274. A CD-ROM driver 276 may be included in the data processing system 200 to read data from the CD-ROM 278 (compact disc read only memory). Said CD-ROM discs 278 use laser optics rather than magnetic means to read data. The mouse controller 280 of the keyboard is provided in the data processing system 200 for interfacing with the keyboard 282 and a pointing device, such as the mouse 284. Such pointing devices are typically used to control an on-screen element., such as a cursor, which can take the form of an arrow that has an intense point that specifies the location of the indicator when the user presses a mouse button. The direct access memory (DMA) controller 286 can be used to provide an access memory that does not include the CPU 250. Such access memories are typically used to transfer data directly between the memory and an "intelligent" peripheral device, such as between RAM 256 and disk controller 266.

The communication between the data processing system 200 and other data processing systems can be facilitated by the serial controller 288 and the network adapter 290, which are coupled to the main transmitting path 254 of the system. The serial 288 controller is used to transmit information between computers, or between a computer and peripheral devices, one bit at a time on an individual line. Serial communications can be synchronous (controlled by some time standard such as a clock) or asynchronous (controlled by the exchange of control signals that determine the flow of information). This serial interface can be used to communicate with the 292 modem. A modem is a communications device that allows a computer to transmit information over a normal telephone line. The modems convert digital computer signals into analog signals suitable for communication over telephone lines. The 292 modem can provide a connection to other software sources, such as a file server, an electronic bulletin board, and the Internet or World Wide Web. The network adapter 290 can be used to connect the data processing system 200 to a local area network (LAN) 294. The LAN 294 can provide users of computers with electronic means of communication and transfer of software and information. Additionally, LAN 294 can provide distributed processing, which involves several computers and the distribution of workloads or cooperative efforts to accomplish a task. The display 296, which is controlled by the display controller 298, is used to display the visual output generated by the data processing system 200. Said visual output may include text, graphics, animated graphics and video. Deployment 296 may be implemented with a CRT-based video display, an LCD-based flat panel display, or a gas plasma-based flat panel display. The deployment controller 298 includes electronic components that are required to generate a video signal that is sent to the display 296. The printer 300 can be coupled to the data processing system 200 by the parallel controller 302. The printer 300 is used to set text or a computer generated image on paper or other medium, such as a transparency. Other types of printers may include an image positioner, an automatic plotter or a film recorder. Parallel controller 302 is used to simultaneously send multiple data and control bits on wires connected between the transmitting main path 254 of the system and another parallel communication device, such as printer 300. The most common parallel interface is the interface Centronics During data processing operations, different devices connected to the main transmitting path 254 of the system can generate interrupts that are processed by the interrupt controller 304. An interruption is a request for attention from the CPU 250 that can be passed. to the CPU 250 using hardware or software. An interruption causes the microprocessor to frequently suspend execution instructions, save the condition of the work in progress, and transfer control to a special routine, known as an interrupt manipulator, which causes a particular series of instructions to be carried out. The interrupt controller 304 may be required to handle a hierarchy of interruption priorities and arbitrate simultaneous interrupt demands. The interrupt controller 304 may also be used for temporarily invalid interruptions. Referring now to Figure 7 of the drawings, a schematic diagram of the component control system of the multi-stage winder 71 is illustrated. The component control system 305 is controlled primarily by computer-readable instructions in the form of software. Said software is executed within the programmable logic controller (PLC) 306 of control to activate the component control system 305. The control PCL 306 retrieves, decodes, executes instructions and transfers information to and from other resources via the main data transfer path of the component control system 305, the main transmitting path 308 of logic control. The main transmitting path 308 of logic control connects the components in the component control system 305 and defines the means for data exchange. The main transmitting path 308 of logic control typically includes data lines for sending data, address lines for sending addresses and control lines for sending interrupts, and for operating the main transmitting path 308 for logic control. The communication between the component control system 305 and the data processing system 200 is facilitated by the serial controller 288 which is coupled to the serial controller 307. The serial controller 288 is used to transmit information between the processing system data 200 and the component control system 305, through the serial controller 307, one bit at a time on a single line. A plurality of digital logic controllers 310, 311, 313, 315, 317 and 319 are in communication with the control PLC 306 via the main transmitting path 308 of logic control. The digital logic controller 310 is in communication with the motor control box 312 which is coupled to, and receives data from, and transmits operation inputs to, one or more winch drive motors 314 of the multi-stage winder 71. The digital logic controller 311 is in communication with the control box of the digital linear encoder 316 which is coupled to, and receives data from, one or more digital linear encoders 117 of the multi-stage winder 71. The digital logic controller 313 is in communication with the control box of the air tension cylinder 318, which is coupled to, and receives data from, and transmits operation inputs to, one or more air tension cylinders 133 of the multi-stage winder 71. The digital logic controller 315 is in communication with the control box of heater arrangement 320 which is coupled to, and transmits operation inputs for, heater arrangements 63, 65, 67 and 68 of the multi-stage winder 71. The digital logic controller 317 is in communication with the pump control box of the heat transfer medium 322 which is coupled to, and receives data from, and transmits. operating inputs for the heat transfer medium pump 324 of the multi-stage winder 71. The digital logic controller 319 is in communication with the control box of the temperature sensing device 323 which is coupled to, and receives data from the , temperature sensing device 326 of the multi-stage winder 71. Each non-woven fabric strip 13, 15, 17 and 19 is composed of selected polymer fibers, such as polyester and polypropylene which can function as base fibers or binder material, or both In general, the base fibers have higher melting points than the binder material. The function of the base fibers is to produce small pore structures in the colorless mucous membrane filter element 11. The function of the binder material is to join the base fibers into a rigid filter element that does not require a separate core. The binder material may consist of pure fiber or fiber having an outer shell of lower melting point and an inner core of higher melting point. If the binder material is of the pure type, then it will completely melt in the presence of sufficient heat. If the binder material has an outer shell and an inner core, then it is subjected to temperatures that melt only the outer shell in the presence of heat, leaving the inner core to facilitate the base fibers to produce small pore structures. Thus, the function of the binder material is to melt totally or partially, in the presence of heat, the liquid fraction of it so that it enters by means of a wick in the base fibers to form a point of union between the base fibers, joining this form the base fibers together after they have cooled. The binder material may be in another form apart from the fibrous form. In the preferred embodiment of the invention, the base fibers and the binder material are mixed according to the manufacturing process set forth in Figure 5 to form rolls of non-woven fabric strips 13, 15, 17 and 19, each of a selected composition. The rolls of nonwoven fabric strips 13, 15, 17 and 19 are loaded onto the roll support arrows 79 of the roll holder 75 at each stage of the multi-stage winder 71. Each roll stand 75 is positioned to introducing the non-woven fabric strips 13, 15, 17 and 19 at a selected angle towards the hollow mandrel 47. Convenient specifications are selected for a multi-overlapped coreless filter element 11, by means of board 282 or mouse 284 of the system data processor 200. According to the software, the UPC 250 retrieves, decodes, executes instructions and transmits the appropriate information to the control PLC 306 of the component control system 305. The control PLC 306 retrieves, decodes, executes instructions and transmits control information to the digital logic controllers 310, 311, 313, 315, 317, 319, which in turn analyze and format the control information. The control information is communicated to the appropriate motor control box 312, tensioner air cylinder control box 318, heater arrangement control box 320, or heat transfer medium pump control box 322, which converts the control information in operational inputs and sends the operation inputs to the appropriate winch drive motor 314, tension air cylinder 133, heater arrangements 63,65,67,68 or heat transfer medium pump 324, each of the which operates and performs work according to the operation inputs. A length of the non-woven fabric strip 13 is unwound and loaded onto the feed tray 81 so that it rests on the channel 84 between the upturned edges 83 and 85 of the feed tray 81. The feed tray 81 is positioned so that the non-woven fabric strip 13 is inserted into the hollow mandrel 47 at a selected angle. In accordance with the operational inputs from the motor control box 312, the winch drive motor rotates the gears of the winch drive gearbox 107 that rotate the winch 105. The slotted arrow of the first stage of the winch machine multistage winding 71 transmits power to the gearbox of the driven winch 109, the gears of which rotate the driven winch 106 at the same angular speed, but in the opposite direction as the driving winch 105. The friction between the inner surface of the compression band 55 and the radially outer surfaces of the driving winch 105 and the driven winch 106 force the band to rotate with the winches 105 and 106 without tangential slip. The flanges 127 and 129 of the winch sleeves 123 and 125, respectively, prevent the compression band 55 from slipping down onto the driven and driven winches 105 and 106, respectively. Then, the nonwoven fabric strip 13 is loaded between the outer annular surface 49 of the hollow mandrel 47 and the compression band 55, at the point at which the compression band 55 makes its single spiral curve around the hollow mandrel 47. Because the frictional drag generated between the compression band 55 and the non-woven fabric strip 13 is greater than the frictional drag generated between the non-woven fabric strip 13 and the hollow mandrel 47, the multi-lapped non-core filter element 11 is formed in a conical helix shape, and is driven along the hollow mandrel 47 towards the free end thereof. The feeding angle between the non-woven fabric strip 13 and the hollow mandrel 47 is such that the non-woven fabric strip 13 overlaps itself a plurality of times as it is compressed between the compression band 55 and the hollow mandrel. 47, producing the multi-overlapping conical helix feature of the present invention. The compressive force supply selected from the compression band 55 is the tension of the compression band 55, which is determined by the distance selected between the axes of the driving winch 105 and the driven winch 106. Since the driving winch 106 is connected to the gearbox of the driven winch 109, which in turn is connected at its base to the sliding plate of the gearbox 115, the driving winch 106 is free to move along the rails of the linear encoder 117. The digital linear encoder 117 is coupled to a digital linear encoder control box 316, by which it transmits data to a digital logic controller 311 and a control PLC 306. The digital linear encoder 117 incrementally measures the location of the digital Driven winch gear box 109 along the rails of the digital linear encoder 117 in relation to a p reference to the digital linear encoder 117, and transmits that information to the component control system 305. The location of the driven winch gear box 109 is transmitted to the component control system 305, whereby the speed of the motor winch driver 314 is calculated and transmitted, through the motor control box 312, to the winch drive motor 314. The compressive force released by the compression band 55 on the non-woven fabric strip 13, is controlled and maintained by a selected pressure in the pneumatic tension air cylinder 133, the arrow 135 of which is connected to the driven sling gearbox 109. The pneumatic tension cylinder 133 is coupled with a tension air cylinder control box 318, by means of which it receives operational inputs from a digital logic controller 313 and a control PLC 306. The pressure in the tension air cylinder ne Umatico 133 is adjusted according to the operational inputs, so that its arrow 135 is extended or retracted to control and maintain the compressive force released by the compression band 55 towards the non-woven fabric strip 13. Applied simultaneously with the mentioned compression formerly for the multi-overlapping nonwoven fabric strip 13, there is a selected amount of heat generated by an infrared heater arrangement 63 located at a selected distance from the nonwoven fabric strip 13. Each infrared heater 63 is connected to a heating actuator plate 101 which provides movement for each infrared heater 63 towards or away from the hollow mandrel 47. The dial adjustment mechanism 99 of the heater actuator plate 101 allows incremental adjustment of the distance between each infrared heater 63 and the hollow mandrel 47. Each infrared heater 63 is coupled to a heater arrangement control box 320, by means of the which receives operational inputs from a digital logic controller 315 and a control PLC 306, for a selected voltage of electricity to be supplied and maintained in each infrared heater 63 for the purpose of heating the strip of non-woven non-woven fabric 13. The strip 13 multi-overlap nonwoven is heated to a selected temperature, so that the base fibers are joined together, both within the strip and between the multi-lapped layers of the web 14 by the process of wicking the material blended binder. As the non-woven fabric strip 13 is heated and compressed simultaneously to produce the desired porosity, a heat exchanging medium is pumped through the cylindrical channel 53 of the hollow mandrel 47, by means of a pumping device (represented schematically in figure 7, number 324) at a flow rate selected for the purpose of maintaining a selected temperature in the outer surface 49 of the hollow mandrel 47. The pumping device is coupled to a pump control box of heat transfer medium 322, whereby it receives the op-rational inputs of a digital logic controller 317 and a control PLC 306 , so that the selected flow rate is imparted to the heat exchanger medium, to maintain a selected temperature on the outer surface 49 of the hollow mandrel 47. One or more temperature sensing devices, such as thermocouples (not shown but schematically depicted in FIG. figure 7, number 326) are in communication with the heat exchanger medium in order to detect the temperature erature of the heat exchanger medium. Each temperature sensing device is coupled to a temperature sensing device control box 323, by means of which it transmits data, relative to the temperature of the heat transfer medium, to a digital logic controller 319 and a control PLC 306. The component control system 305 continuously receives and analyzes signals from the sling drive mo314, digital linear encoder 117, tension air cylinder 133, heat transfer medium pump 324, and temperature sensing device 326, enabling that the component control system 305 continuously transmit updated operational inputs to the sling drive mo314, tension air cylinder 133, heating arrangements 63, 65, 67 and 68, and heat transfer medium pump 324. The transmitted data of the digital linear encoder 117 of each stage of the multistage winding machine 71, is used to calculate and determining the appropriate speed of the sling-drive mo314 of each stage, thereby synchronizing the speed of each sling-driving mo314, with the sling-drive mo314 of the first stage. The woven fabric strip 13 continues to overlap itself, thereby forming the web 14 which is driven along the hollow mandrel 47 through the openings 139 of the heater array supports 137 of each remaining stage of the machine of multistage winding 71, in a continuous endless manner. Once the band 14 has passed through all the stages of the multi-stage winding machine 71, the non-woven fabric strip of the second stage 15 is loaded between the feed tensioning rollers 147 of the feed tensioner of the second stage 141. The nonwoven fabric strip 15 is then loaded between the compression band 57 and the annular outer surface of the band 14 at the point where the compression band 57 makes its only spiral around the hollow mandrel 47. The non-woven fabric strip 15 is compressed and heated simultaneously by identical means as the non-woven fabric strip of the first stage 13. The non-woven fabric strip 15 continues to be overlapped on itself, thereby forming the strip 16, the inner annular surface of which is attached to the annular outer surface of the band 14. The combined bands 14 and 16 are driven along the hollow mandrel 47, through the openings 139 of the brackets of the device. heating station 137 of each remaining stage of the winding machine 71, in a continuous, endless manner. Once the combined webs 14 and 16 have passed through all the remnant steps of the multistage winding machine 71, the non-woven web strip 17 is unwound and loaded between the feed web tensioning rollers 147 of the web tensioner. third stage feed 141. Then, the non-woven fabric strip 17 is loaded between the compression band 59 and the annular outer surface of the band 16 at the point at which the compression band 59 makes its only spiral around the hollow mandrel 47. The non-woven fabric strip 17 is compressed and heated simultaneously by means identical to those of the non-woven fabric strip of the first stage 13. The non-woven fabric strip 17 continues to be overlapped on itself, thereby forming the band 18, the annular surface of which is joined on itself, thereby forming the band 18, the inner annular surface of which is attached to the outer annular surface of the band 16. The combined bands 14 , 16 and 18 are driven along the hollow mandrel 47 through the openings 139 of the heater array supports 137 of the remaining stages of the multi-stage winding machine 71, in a continuous endless manner. Once the combined webs 14, 16 and 19 have passed through the rest of the stages of the multi-stage deburring machine 71, the non-woven fabric strip 19 is loaded between the feed tensioning rollers 147 of the feed tensioner of the fourth stage 141. Then, the non-woven fabric strip is loaded between the compression band 61 and the annular outer surface of the band 18 at the point at which the compression band 61 makes its single spiral around the hollow mandrel 47. The strip of non-woven fabric 19 continues to be overlapped on itself, thereby forming the band 20, the inner annular surface of which is attached to the outer annular surface of the band 18. The combined bands 14, 16, 18 and 20, are driven along the hollow mandrel 47 in a continuous endless fashion towards a measuring device (not shown) and a cutting device (not shown). Once the combined bands 14, 16, 18 and 20 have passed through the final stage of the multistage deburring machine 71, the multi-layered non-core filter element 11 is measured by the measuring device and cut out to the length by means of the cutting device. The angular velocity of the winch drive motor 314 is such that the non-woven fabric strips 13, 15, 17 and 19 remain in sufficient proximity to the infrared heaters 63, 65, 67 and 68 for a selected duration of time, way to allow adequate liquefaction of the binder material. Sufficient distance is provided between the stages, so that the binder material is allowed to partially cool, thereby bonding the base fibers within each non-woven strip 13, 15, 17 and 19; between each layer of them; and between each band 14, 16, 18 and 20; providing the desired porosity between each layer and between each band 14, 16, 18 and 20. The simultaneous application of selected amounts of heat and compression to the layers of non-woven strips 13, 15, 17 and 19, is such that only the Selected properties are altered, resulting in a multi-overlapped coreless filter element 11, with sufficient structural strength to self-seal, ie, it does not require a structural core, while maintaining the desired porosity. Furthermore, the simultaneous application of selected amounts of heat and compression to the non-woven fabric strips 13, 15, 17 and 19, as described above, allows the systematic variation of the density of the layers of non-woven fabric strips 13, 15, 17 and 19, through the wall of the non-core, multi-overlapping filter element 11, and the systematic variation of the resulting porosity of the base fibers. The flow direction of the filtrate through the multi-lapped non-core filter element 11 can be from the core to the outer annular wall, or from the annular outer wall towards the core, but in any case, the filtrate flow through it is generally perpendicular to the axis of the multi-lapped filter element 11. However, due to the conical helix nature of the layers of the non-woven fabric strips 13, 15, 17 and 19, the pores that are formed by the bonded base fibers are angled to the axis of the filter element without multi-overlap center 11 making it more difficult for large particles of the filtrate to pass through the filter element without multi-overlap center 11. The filter element without center multi-overlap 11 may be completed by finishing ends 25 and 27 by any suitable means known to those skilled in the art, such as wet vaporization of a polymeric resin. A wire activated switch (not shown) extends the entire length of the multi-stage winder 71 for the purpose of interrupting the operation of said machine in case of emergency. The following is an example of the method and means for manufacturing a filter element without multi-overlap center 11 of the type shown in Figure 1: Four different types of fibers were purchased at Hoechst Celanese in Charlotte, North Carolina, which They were sold under the designation of fibers "252", "121", "224", and "271". The "252" fiber was of the center and shell type, while the fibers "121", "224", and "271" were of the pure one-component type. The fiber denier "252" was 3 and its length was 37 meters. The denier of the fiber "121" was 1 and its length was 37 meters. The denier fiber "224" was 6 and its length was 50 meters. The fiber denier "271" was 15 and its length was 15 meters. A first fiber mixture was made from the fiber "121", and the fiber "252" composed of 50% by weight of each fiber type. A second fiber mixture was made from the "224" fiber and the "252" fiber composed of 50% by weight of each fiber type. A third fiber blend was made with a composition of 25% by weight of fiber "121" and 25% by weight of fiber "224" and 50% by weight of fiber "252". A fourth fiber blend was made from fiber "271" and fiber "252" composed of 50% by weight of each fiber type. In each of the aforementioned mixtures the "252" fiber, of the type with center and cover, served as binder material. Each fiber mixture was manufactured according to the procedure set forth in Figure 5. Each fiber mixture was formed into a belt, which was about 1.3 centimeters thick. The thickness of each belt was reduced by about 50% by forming a thin nonwoven sheet during its 90 second residence time in the air suction ovens due to the recirculation of steam saturated air to approximately 18, 877.48 liters per second, at a temperature of 204.4 ° C. There was a differential pressure of 15 centimeters of water through the thin nonwoven sheet in the air suction ovens. After leaving the air aspiration furnaces, each thin non-woven sheet advanced between two stainless steel cylindrical rolls which compressed the thickness of each non-woven thin sheet by approximately 50% to make it a non-woven fabric with a width of approximately 92.5 centimeters. Each 92.5 cm wide non-woven fabric was cut into strips, 13, 15, 17 and 19, about 15 centimeters wide. The base weight of each non-woven fabric was determined, which was in the range of 152.57 to 366.18 grams per square meter. As a step to ensure quality, once each non-woven fabric was cut into the non-woven fabric strips 13, 15, 17, and 19, these were tested in a Frasier air flow tester to determine permeability to the air in cubic meters per minute per square meter. The nonwoven fabric strips 13, 15, 17 and 19 were then loaded onto the roll supporting arrows 79 of the roll holders 75, one roll at each stage of the multi-stage winder 71. The specifications of the strips of non-woven fabric 13, 15, 17 and 19 were entered into the data processing system 200 with keyboard 282 and cursor 284. Hollow mandrel 47 was made of stainless steel and had a nominal outside diameter of 2.5 centimeters. The heat transfer medium pumping device 324 was turned on and started pumping heat transfer medium through the hollow mandrel 47 at variable flow rates such that the temperature of the annular outer surface 49 of the hollow mandrel 47 was maintained at 93.3 ° C, in accordance with the data transmitted from the temperature sensing device 326 to the component control system 305 and to the operational inputs of the component control system 305. The winch drive motor of the first stage 314 was set at run at a control speed of approximately 50 hertz, as instructed by the component control system 305. The first stage heater arrangement 63 was turned on and supplied with a sufficient voltage of electricity to create a temperature of 148.8 ° C in the mandrel. hollow 47. The first strip 14 of non-woven fabric strip 13 was started by advancing the strip of non-woven fabric 13 between the mandrel hollow bar 47 and the first stage compression band 55. The nonwoven web 13 was spirally wound over itself forming the web 14 as it passes under the compression band 55 and through the mandrel. hollow 47. As the outer diameter of the band 14 increased, the driving winch 106 moved towards the driving winch 105 so that the distance between them would shorten and maintain a pressure of 70 kilograms per square centimeter exerted on the band 14 from the compression band 55. This compression pressure was a result of the tension in the compression band 55, which was developed by the pressure of 350 kg / cm2 gauge in the air cylinder of the tensioning mechanism 133. The movement of the driving winch 106 was performed by altering the pressure in the air cylinder of the tensioning mechanism 133. The digital linear encoder 117 detected the movement of the driving winch 106 thereby transmitting the outer meter of the band 14 to the component control system 305 so that said system could make the appropriate modifications to the speed of the driving motor of the winch 314. The temperature created by the infrared heater 63 was the temperature "about to be ironed" . This ironing point temperature of 148.8 ° C aided in the compression and ligation of the base fibers between the layers of the web 14. Under this simultaneous application of heat and compression, the thickness of the strip of non-woven fabric 13 was compressed in approximately 50% and there was an interlayer linkage. Band 14 was allowed to travel through each stage of the multi-stage winder 71 and before finding the compression band at each stage, the winch drive motor of that stage was turned on and set at the speed of the winch driving motor of the first stage 314 by means of operational inputs of the component control system 305. Once the band 14 passed through all the stages of the multi-stage winder 71, the second strip 16 of non-woven fabric strip 15 was started by passing the strip of non-woven fabric 15 between the compression band 57 of the second stage and the annular outer surface of the band 14. The non-woven fabric 15 was spirally wound over itself to form the web 16 after passing under the compression band 57 and the hollow mandrel 47. The heater arrangement 65 of the second stage was turned on and supplied a voltage of 148.8 ° C on the annular outer surface of the strip 16. When the outer diameter of the strip 16 increased, the driven winch of the second stage moved towards the winch second stage impeller to shorten the distance between them and maintain a pressure of 70 kg / cm2 exerted on the band 16 from the compression band 57. This compression pressure was the result of the tension in the compression band 57 , which was developed by the pressure of 350 kg / cm2 gauge of the air cylinder of the tensioning mechanism of the second stage. The movement of the winch driven from the second stage was carried out by altering the pressure in the air cylinder of the tensioning mechanism of the second stage. The digital linear encoder of the second stage detected the movement of the driven winch of the second stage thus transmitting the outside diameter of the band 16 to the component control system 305, so that the component control system 305 could make appropriate modifications to the speed of the winch drive motor of the second stage to synchronize the speed of the winch drive motor of the second stage with the winch drive motor of the first stage 314. The ironing point temperature of 148.8 ° C aided the compression and bonding of the base fibers between the layers of the strip 16. Under this simultaneous application of heat and compression, the thickness of the nonwoven tile strip 15 was compressed by approximately 50% and interlayer linkage was achieved. The annular r surface of the band 16 was bonded to the annular outer surface of the band 14 and the band 16 advanced through the hollow mandrel 47 towards the compression band 59 of the third stage. The band 15 was allowed to travel through the remaining stages of the multi-stage winder 71 and before finding the compression band in each stage, the winch drive motor of that stage was turned on and set at the speed of the stage. winch drive motor 314 of the second stage by means of operational inputs of the component control system 305. Once the band 16 advanced through all the stages of the multi-stage winder 71, the third band 18 of fabric nonwoven 17 was started by advancing the non-woven fabric strip 17 between the compression strip 59 of the third stage and the annular outer surface of the strip 16. The non-woven fabric 17 was spirally wound overlapping on itself forming the band 18 passing under the compression band 59 and the hollow mandrel 47. The heater arrangement 67 of the third stage was turned on and supplied with an electric voltage d sufficient to maintain an ironing temperature of 148.8 ° C on the outer annular surface of the band 18. As the outer diameter of the band 18 increased, the driven winch of the third stage moved towards the latter's driving winch step to shorten the distance between them and maintain a pressure of 70 kilograms per square centimeter exerted on the band 18 from the compression band 59. This compression pressure was a result of the tension in the compression band 59, which was developed by the pressure of 350 kg / cm2 gauge of the air cylinder of the tensor mechanism of the third stage. The movement of the winch driven from the third stage was carried out by altering the pressure of the air cylinder of the tensor mechanism of the third stage. The digital linear encoder of the third stage detected the movement of the driven winch of the third stage thus transmitting the outer diameter of the band 18 to the component control system 305 so that said system could make appropriate modifications to the speed of the driving motor of the third stage. winch of the third stage synchronize the speed of the winch drive motor of the third stage with the winch drive motor of the first stage 314. The ironing point temperature of 148.8 ° C helped the compression and ligation of the fibers of base between the layers of the strip 18. Under this simultaneous application of heat and compression, the thickness of the strip of non-woven fabric 17 was compressed by approximately 50% and interlayer ligation occurred. The annular inner surface of the band 18 was bonded to the annular outer surface of the band 16 and the band 18 advanced through the hollow mandrel 47 towards the compression band 61 of the fourth stage. The band 18 was allowed to travel through the remaining stage of the multi-stage winder 71 and before finding the compression band 61 of the fourth stage, the winch drive motor of the fourth stage was set at the speed of the second stage. winch driving motor of the third stage by means of operational inputs of the component control system 305. Once the band 18 advanced through the remaining stage of the multi-stage winder 71, the fourth strip 20 of The non-woven fabric 19 was started by passing the non-woven tile strip 19 between the compression band 61 of the fourth stage and the annular outer surface of the strip 18. The non-woven fabric strip 19 was wound in an overlapping fashion over it itself forming the band 20 by passing under the compression band 61 and the hollow mandrel 47. The heater arrangement 68 of the fourth stage was ignited and supplied with an electri enough to maintain an ironing temperature of 148.8 ° C on the annular outer surface of the band 20. When the outer diameter of the band 20 increased, the driven winch of the fourth stage moved into the driving winch of the fourth stage. step to shorten the distance between them and maintain a pressure of 70 kilograms per square centimeter exerted on the band 20 from the compression band 61. This compression pressure was the result of the tension in the compression band 61, which was developed by the pressure of 350 kg / cm2 gauge in the cylinder of air tensioner of the fourth stage. The movement of the driven winch of the fourth stage was completed by altering the pressure of the air-tensioning cylinder of the fourth stage. The digital linear encoder of the fourth stage detected the movement of the driven winch of the fourth stage, thus transmitting the external diameter of the band 20 to the component control system 305 so that appropriate modifications could be made to the speed of the driving motor of the fourth stage. winch of the fourth stage by the component control system 305 to synchronize the speed of the winch drive motor of the fourth stage with the winch drive motor of the first stage 314. The ironing point temperature of 148.8 ° C it assisted in the compression and bonding of the base fibers between the layers of the strip 20. Under this simultaneous application of heat and compression, the thickness of the strip of non-woven fabric 19 was compressed by approximately 50% and there was the bond between layers. The inner annular surface of the band 20 was attached to the outer annular surface of the band 18 and the filter element without multi-overlap center 11 advanced along the hollow mandrel 47 towards the measuring and cutting devices, where it was measured and cut to a length of 762 mm. The resulting filter element 11 had a nominal internal diameter of 25.4 mm, a nominal external diameter of 63.5 mm and was 762 mm long. It weighed 0.373 kg and had an air flow capacity of 9.44 liters per second, producing a water column differential pressure of 124.46 mm. In an alternative embodiment of the invention, a conductive strip may be included in one or more stages of the multistage winding machine 71 to keep the hollow mandrel 47 in a properly fixed position. In an alternative embodiment of the invention, a plurality of nonwoven fabric strips are added in a single step of the multistage winding machine 71. Although the invention is shown only in one of its forms, not only is it not limited but which is susceptible to various changes and modifications without departing from the spirit of the same.

Claims (24)

NOVELTY OF THE INVENTION CLAIMS

1. - A filter element comprising: a non-woven fabric comprising a substantially homogeneous mixture of a base fiber and a binder material compressed to form a sheet of selected porosity; the binder material has at least one surface with a melting temperature lower than that of the base fiber; the sheet is given a selected geometric shape; The base fiber and the binder material are thermally melted at a temperature that melts at least the surface of the binder material to bind the base fibers, when the sheet is cooled, and create a porous filter element.

2. The filter element according to claim 1, further characterized in that the sheet is wound spirally and compressively to form a tubular filter element, the binder material being a fiber.

3. The filter element according to claim 2, further characterized in that said sheet is helically wound and overlapped to a degree to form a laminate of selected thickness.

4. The filter element according to claim 3, further comprising: a second non-woven fabric comprising a substantially homogeneous mixture of a base fiber and a binder material, compressed to form a sheet of selected porosity; the first of said sheets forms a first layer and the second of said sheets forms a second layer, wrapped in a pattern similar to the first layer and overlapping the first layer to form a laminate of alternating layers of the first and second sheets.

5. The filter element according to claim 4, further characterized in that said first and second sheets have different porosities.

6. The filter element according to claim 5, further characterized in that said binder material is selected from the group consisting of thermoplastic material and resin; and said base fiber is selected from the group consisting of thermoplastic and natural material.

7. A method for manufacturing a filter element comprising the steps of: forming a non-woven fabric comprising a substantially homogeneous ribbon of a base fiber and a binder material, compressed to form a sheet of selected porosity; the binder material has at least one surface with a melting temperature lower than that of the base fiber; heating said sheet to liquify at least the surfaces of the binder material; cooling the sheet to achieve a thermal fusion of the tape and to form a porous filter element.

8. The method according to claim 7, further comprising the steps of: wrapping said sheet before heating it around a mandrel in a self-overlapping style to form a tubular laminate; Cut the tubular filter element to a selected length.

9. The method according to claim 8, further characterized in that said envelope is made spiral and is compressed.

10.- The method according to the claim 9, which further comprises the additional step of: wrapping, before the heating step and the subsequent steps, a second non-woven fabric of porosity selected around the first of said sheets of material in an overlapping style to form a second layer, licking on the first layer, said second sheet being formed of a second filter material of selected porosity; The binder material of said first sheet has at least one surface with a melting temperature lower than that of the base fiber.

11. The method according to the claim 10, in which said envelope of the first of said sheets and of the second of said sheets is helical, with an overlap to form two layers of selected thickness.

12. The method according to the claim 11, further comprising the steps of compressing each layer individually during the wrapping step.

13. The method according to claim 12, further comprising the step of heating at least the first sheet after being wound on said mandrel.

14. The method according to the claim 13, further characterized in that said binder material is selected from the group consisting of thermoplastic material and resin; and said base fiber is selected from the group consisting of thermoplastic and natural material.

15.- The method according to the claim 14, further comprising the step of radiant and individually heating each layer while it is wrapped.

16. A machine for manufacturing a filter element comprising: means for forming a non-woven fabric comprising a substantially homogeneous ribbon of a base fiber and a binder material, compressed to form a sheet of selected porosity; the binder material has at least one surface with a melting temperature lower than that of the base fiber; means for heating said sheet to liquify at least the surfaces of the binding fibers; means for cooling the sheet to achieve thermal fusion of the tape and to form a porous filter element.

17. The machine according to claim 16, further comprising: means for wrapping said sheet before heating it around a mandrel in a self-tracking style to form a tubular laminate; means for cutting the tubular filter element to a selected length.

18. - The machine according to claim 17, further characterized in that said envelope is made spiral and is compressed.

19. The machine according to claim 18, comprising means for wrapping, before the heating step and the subsequent steps, a second sheet of non-woven fabric of porosity selected around the first of said sheets in an overlapping style to form a second layer, laminated on the first layer, said second sheet being formed of a substantially homogeneous ribbon of a base fiber and a binder material; means for compressing the second sheet to a selected porosity; The binder material of said second sheet is formed of a material having at least one surface with a melting temperature lower than that of the base fiber.

20.- The machine in accordance with the claim 19, further characterized in that said envelope of the first of said layers and of the second of said layers is helical, with overlap to form two layers of selected thickness.

21.- The machine in accordance with the claim 20, further comprising means for compressing each layer individually during the wrapping step.

22. The machine according to claim 21, further comprising means for heating each sheet after it has been wound on said mandrel.

23. - The machine in accordance with the claim 22, further characterized in that said binder material is selected from the group consisting of thermoplastic material and resin; and said base fiber is selected from the group consisting of thermoplastic and natural material. 24.- The machine in accordance with the claim 23, further comprising means for radiant and individually heating each layer while it is wrapped.