MXPA00011476A - Stack filter assembly and methods - Google Patents

Abstract

An air cleaner arrangement useful for cleaning air in ablative thermal imaging processes includes a housing (fig.3-45) and a removable and replaceable element assembly (fig.3-50). The housing has an interior, an inlet conduit (fig.3-24), and an outlet conduit (fig.3-28). The element assembly includes first (fig.3-52) and second (fig.3-54) filter elements axially aligned and secured together in a stack configuration. The first filter element has a media pack (fig.3-60) for filtering particulate material. The second filter element has a media pack for (fig.3-64) filtering noxious gases, such as formaldehyde. In operation, a blower assembly (fig.1-16) directs airflow through the inlet conduit, into the first element interior, through the first element media pack, through the second element media pack, into the second element interior, and out through the housing outlet conduit. Methods for filtering and changing out of the element assembly are also described herein.

Description

ASSEMBLY AND METHODS OF STACKED FILTER Field of the Invention This invention involves filtering arrannts and methods. In a specific application, this invention involves an arrannt and filtering method to remove particulates and gases emitted during the ablation processes of thermal imaging.

BACKGROUND OF THE INVENTION In certain types of printing processes, an image is captured in a film through a photographic technique. Chemical solutions are applied to the film to develop and burn the image on a plate. The plate is then used in a printing press. This type of printing process is increasingly replaced with computerized plate technology (CTP). In CTP technology, an image is captured digitally. The digital image is transmitted to a laser that acts on a film. The film usually has a dye coating laminated on a plastic film. For example, the films are commercialized by Kodak and DuPont. E-l laser burns or wears Ref. 125015 the dye coating to form the image. The film with the image is then exposed and printed on a plate. The plate is then used in a printing press. This process is also called a thermal ablation imaging process. When the laser burns the dye coating on the film, certain gases and contaminants or acroparticles are emitted. Gases may include: formaldehyde. for example, or smells like sulfur. It is desirable to clean the air with the help of CTP technology.

Brief Description of the Invention A filter arrannt is provided that includes the first and second intermediate structures. The first and second intermediate structures are preferably stacked in axial alignment. The first intermediate structure preferably operates to remove the particulates from an airflow stream. The second intermediate structure preferably operates to remove odors or gases from an airflow stream. Preferably, the second intermediate structure is positioned to be running downstream of the first intermediate structure.

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Preferably, the first intermediate structure has first and second opposed end covers and an open filter interior. The first outer cover preferably has an opening d € > air flow in fluid air communication with the internal air filter, of the open filter, while the second external cover closes to the air flow a. through it. Preferably, the second intermediate structure has first and second opposite end covers and define an interior of the open filter. Preferably, the first end cover of the second intermediate structure is closed to the air flow through it and is adjacent to the second end cover of the first intermediate structure. Preferably, the second end cover of the second intermediate structure has an air flow opening in fluid air communication with the interior of the open filter of the second intermediate structure. In a preferred arrannt, the air flow stream to be filtered is directed into the interior of the open filter of the first intermediate structure, through the first medium, through the second medium, into the interior of the open filter of the second intermediate structure. , and outside through the opening of the air flow in the second end cover of the second intermediate structure. In certain preferred embodiments, the filter element arrannt is oriented within a housing. Preferably, a sealing system is used to provide a tight seal between the arrannt of the element and the housing. The sealing systems may include axial sealing systems or radial sealing systems. Methods for filtering and changing a filter element assembly are provided. Preferred methods may use certain preferred arrannts as described herein.

BRIEF DESCRIPTION OF THE DRAWINGS FIGURE 1 is a schematic illustration of one embodiment of an air purifying system, in accordance with the principles of the present invention. FIGURE 2 is a perspective view of an embodiment of an air purifier, according to the principles of the present invention. FIGURE 3 is a cross-sectional view of the air purifier described in FIGURE 2, and showing an element assembly oriented herein.

FIGURE 4 is a perspective view of one embodiment of an assembly of the element usable in the air purifier described in FIGURE 2, in accordance with the principles of the present invention. FIGURE 5 is a cross-sectional view of the assembly of the element described in FIGURE 4, and showing a first filter element stacked adjacent to a second filter element. FIGURE 6 is a plan view of the assembly of the element described in FIGURES 4 and 5, and showing an outlet conduit and a seal member, in accordance with the principles of the present invention. FIGURE 7 is a side elevational view of the air purifier described in FIGURE 2, differential pressure switches schematically described, according to the principles of the present invention. FIGURE 8 is a bottom plan view of the. air purifier described in FIGURE 1, and showing the assembled structure, according to the principles of the present invention. FIGURE 9 is a fragmented, enlarged, cross-sectional view of the second filter element described in FIGURE 5, in accordance with the principles of the present invention.

FIGURE 10 is a cross-sectional view of an alternative embodiment of an analogous air purifier in the view shown in FIGURE 3, and 'showing a radial sealing system. FIGURE 11 is a fragmentary, cross-sectional view describing an end cover that seals the profile of the area for the radial seal system used in the arrangement of FIGURE 10.

Detailed description of the Preferred Modalities I. Some Problems With Existing Arrangements Filtration systems have been used in the past in relation to ablation processes of thermal imaging. The systems have normally included an open element at both ends, which comprise a macroparticle filter medium radially within a carbon filter medium. The filter element is secured to the housing through a yoke or central joint and a wing nut. Air is directed into the housing inlet, inside the particulate filter, through the particulate filter medium, through the carbon filter medium, and out through the outlet into the housing. The output is normally positioned on the side of the jt &? B-h ^? fa »iJ ri B > Sfa? -. accommodation. There was no method to determine if the filter element needed to be replaced, or if the filter element was not installed in the housing assembly.This arrangement presented problems, for example, the relative orientation of the airflow outlet in the side of the housing sometimes caused a non-uniform flow through the filtration medium.Also, to replace the filter element requires removal of the wing nut and cover.The wing nut constitutes a loose part that could be dropped In addition, the orientation of the particulate filter radially upstream of the carbon filter sometimes leads to loading problems, for example, when the particulate filter medium is charged, the flow The resulting air through the carbon filter medium upstream of the particulate filter medium can be altered and be less uniform. That is, the carbon filter medium immediately downstream of a charged portion of the particulate filter medium will not receive as much air flow therethrough. A) Yes, the air flow will be diverted to other regions of the carbon filter medium and will wear out more than the region of the carbon filter medium immediately adjacent to and downstream of the charged particulate filter medium. In addition, because the element of the filter had openings in both ends, existing problems during the change or repair of the system. During the change, the collection of the particulate can fail through the openings in the housing or in other, undesirable places. The arrangements and methods described here help to solve these and other problems.

II. THE ARRANGEMENTS OF FIGURES 1-10 A. Global System Appreciation Now with reference to FIGURE 1, an air purifying system is shown schematically with the number 10. In FIGURE 1, a process that produces macroparticles and harmful gases as products they are generally shown with the number 12. The process 12 may be, for example, a thermal imager ablation process. The processes normally produce macroparticles within the size range of 0.1 microns and larger and may include sulfur, silica, carbon, aluminum, phosphorous, and / or zinc, depending on the film used. These processes can also; produce gases such as formaldehyde in the amount of 0.5-7.5 parts per million, at room temperature (approximately 22.22 ° C (72 ° F)), depending on the flow velocity. As the velocity drop: flow, the concentration of gases, such as formaldehyde, increases. Normally, the structure is oriented close to] process 12, to direct the air in the vicinity of]. process through the air purifier 20. This can be done by a cover or a nozzle 14 in the vicinity of the process 12. A ventilation chamber 16 induces vacuum pressure through the air purifier and upstream to the region of the nozzle 14, to extract the particulates and fumes in the air purifier 20. The particulates and fumes are extracted in, then, by vacuum pressure in a conduit, such as a flexible hose 22. The hose 22 is in fluid communication (ie, communication of the air flow) with an inlet conduit 24. The hose 22 and the inlet conduit 24 can be sealed! by any suitable means, such as a hose clamp 26. From the inlet conduit 24, the air content of the particulates and noxious gases are directed into the air purifier 20. E] air purifier 20 removes by air less about 90% and usually at least 95% of the total particulate having a larger size; 0.5 microns, and eliminates 90% at least and usually at least 98.7% of the gases of formaidehide from the air. The purified air is then extracted through an outlet duct 28, where it is eventually directed through the ventilation chamber 16 and into the atmosphere. A hose 30 can normally be used to connect the outlet conduit 28 to the ventilation chamber 16. Again, a hose clamp 32 can be used to maintain a seal secured between the outlet conduit and the hose 30. Turning now to the FIGURE 2, the air purifier 20 is shown in a perspective view. In general, the air purifier 20 includes a housing 45 with a body 46 and a removable cover 47. The inlet conduit 24 can be seen passing through the cover 47. The attention is now directed to FIGURE 3. FIGURE 3 describes a cross-sectional view of the air purifier 20. As can be seen in FIGURE 3, the air purifier 20 includes the housing 45 which retains or contains within it an element of assembly 50. Preferably, mounting member 50 includes a first member 52 secured in axial alignment and stacked on a second member 54. Note; that the inlet conduit 24 is shown extending and projecting through the cover 47 and in ur inner of the open filter 56 of the first element 52. Note also that the outlet conduit 28 is shown extending from the housing body 46 and in communication of air flow with an interior of the open filter 58 of the second element 54. In general, in operation of the air purifier 20, the air containing the particulates and the noxious gases are preferably entrained through the inlet conduit 24, in the inside the open filter 56 of the first element 52, through the means 60 of the first element 52, and in the channel 62 between the housing 45 and the element assembly 50. Preferably, the first element 52 operates to remove the particulates from the air stream. By channel 62, the air stream is preferably directed through the medium 64 of the second element 54, and inside the open filter 58. The medium 64 of the second element 54 preferably operates to remove harmful gases, such as formaldehyde, from the air current. For the inner open filter 58, the purified air flows through the outlet duct 28, and eventually through the ventilation chamber 16 to the atmosphere. B. Element assembly 50 Attention is now directed to FIGURE 4. In FIGURE 4, a mounting of the preferred element 50 is: shown in perspective view. As can be seen, the element assembly 50 preferably includes a cylindrical array comprising the first element 52 axially aligned and stacked on the second element 54. The element assembly 50 is removable and replaceable within the housing 45. As described in FIG. FIGURE 4, the element assembly 50 preferably includes a handle 75 operably connected thereto. The handle 75 helps to remove and orient the element assembly 50 relative to the housing 45. The first and second elements 52, 54 are secured and stacked in axial alignment. By "stacked in axial alignment", it is understood that the first and second filter elements 52, 54 are axially aligned, where they preferably share a common central axis 78 (FIGURE 5), but do not align radially. Rather, they are stacked, one on top of the other, if they are oriented vertically as in the illustration shown in FIGURES 4 and 5.

By "removable and replaceable", it is understood that the element assembly 50 can be removed from the housing 45 without destroying the housing 45. The assembly of the element 50 can then be replaced with a new one, without using the element assembly, which is oriented inside. of accommodation 45 for the operation. E. L worn mounting element 50 can be discarded or recycled, as appropriate. In the preferred embodiment shown, the element assembly 50 comprises the first element 52 secured and stacked on the second element 54. Preferably, the first and second elements 52, 54 are secured by spot welding the end covers of the element between yes. That is, the second end cover 96 (FIGURE 5) of the first element 52 is welded in points to the first end cover 120 (FIGURE 5) of the second element 54. Attention is drawn to FIGURE 5. In FIGURE 5 , the element assembly 50 is shown in cross section. Preferably, the first element 52 is cylindrical and includes internal and external liners 90, 91 to support the filtration means 60. The internal and external liners 90, 91 may include a variety of materials to provide the rigid support structure. These ^^ _ ^ ¡jgsí ^^^ s ^^^^^ may include extended metal, perforated metal, and plastic coatings, as examples. In general, the inner and outer liners 90, 91 should preferably be selected from appropriately perforated materials or otherwise made; porous so as not to substantially interfere with flow; air through the arrangement, and must be of appropriate structural rigidity and strength to contain the intermediate structure and provide the arrangement with sufficient axial force for convenient use and stop, protecting the intermediate structures from damage. Normal coatings will have an open area of chicken minus fifty percent, often sixty percent or more. Galvanized metal or plastic arrangements are usually preferred. At the opposite ends of the filter element 52 are preferably the first and second opposite end covers 95, 96. In the preferred arrangement shown, the medium 60, the inner liner 90, and the outer liner 91 extend between the end covers 95 , 96 and they are insured in them. The particular preferred arrangements shown use end covers 95, 96 formed of metallic material, with the medium 60 and the coatings 90, 91 secured to the end covers 95, 96 by the impregnation material with resins in the liquid state such as polyurethane or epoxy. Still with reference to FIGURE 5, it is understood that the second end cover 96 is a "closed" end cover. That is, the end cover 96 does not include any airflow opening therein, so that, in general, air is prevented from flowing through the end 97 of the interior 56 to the channel 62 (FIGURE 3). In contrast, the first end cover 95 is an "open" end cover, having a central opening 100 therein. In use, the first filter element 52 is secured within the air purifier 20 with the opening 100 circumscribed to the inlet conduit 24 (FIGURE 2). As a result of proper sealing (by means of a variety of possible ways) for the designs as shown in FIGURES 3 and 4, the air flow is inhibited from reaching the channel 62 without first being filtered through the medium 60. For the arrangement shown in FIGURE 4, preferably the sealing system includes an axial sealing system. In particular, a sealing member 106, for example, an O-shaped ring 107 is mounted on the first end cover 95 and circumscribed to the opening 100. The O-shaped ring 107 is compressed within the housing 45, preferably by the cover 47, to form a seal 110 (FIGURE 3, in between .. While a variety of materials can be used for the O-ring 107, preferably a neoprene EPDM SBR sponge rubber material is used.This material is described in detail Further, as shown in FIGURE 3, a gasket 108 can secure the inlet conduit 24 by means of a plate 103 to provide some seal on the seal 109 between the inlet conduit 24 and the first end cover 95. It should be understood, however, that the axial sealing system of the; Board 106 is the reliable main sealing system, in the preferred arrangements. In alternative embodiments, a radial seal can be used between the inlet conduit 2 and the opening 100. An appropriate radial sealing arrangement is more fully described in European Patent 0 329659 Bl, incorporated herein by reference. FIGURE 10 shows an example embodiment of a radial sealing arrangement. This is described below, together with FIGURE 10. Preferably, the first filter element 52 operates as a macroparticle filter, i.e., the first element 52 removes particles such as sulfur, silica, carbon, aluminum, phosphorus, and / or zinc to improve the quality of the printed film or plate in the process 12 (FIGURE 1). The medium 60 is preferably a folded medium, but other alternatives are contemplated. A description of an example of preferred material for the medium 60 is further described below. While the air flow through the inlet conduit 24 and inside the filter 5 (5 carrying the particles and the noxious gases, they pass through the medium 60. Preferably, the medium 60 removes the particles having a larger size. It can be appreciated that the particulates and contaminants are collected on the inner surface of the medium 60. In this way, when the particulates are collected and accumulated, they remain inside the filter 56. This helps in the convenient arrangement and cleaning, by changing the element assembly 50. Because the end cover 96 is a closed end cover, the collected particulate matter remains within the interior 56 of the element 52, during the change in. Still with reference to FIGURE 5, the second filter element 54 is preferably shown in axial alignment with and stacked under the first element '52. As can be seen in FIGURE 5, the The element 54 is preferably cylindrical in shape and has an outer diameter equal to the outer diameter of the cylindrical of the first filter element 52. The second filter element 54 preferably has an axial length considerably shorter than the axial length of the first filter element. 52. This is because, in the preferred arrangements, the amount of medium 64 needs to absorb the noxious odors and gases not being as many as the medium 60 needs to remove the macroparticle. Preferably, the second filter element 54 is oriented downstream of the first filter element 52. In this way, after the air has passed through the medium 60 and has been removed from the particulates, the air then passes through the means 64 in the second filter element 54 to eliminate harmful gases, such as formaldehyde. The second filter element 54 preferably includes a cylindrical inner liner 112 and an outer cylindrical liner 113 for supporting the medium 64. Preferably, the medium 64, the inner liner 112, and the outer liner 113 extend between the first and second end covers 120, 121. Aligning the inner liner 112 is an intermediate internal lining 114, in the preferred systems. áfo ..

Similarly, the alignment of the exterior cladding 113 is an intermediate containment cladding. 115. The intermediate containment liners 114 and 115 preferably also extend between the first and second end covers 120, 121. The internal and external intermediate containment liners 114, 115 preferably operate to assist in holding or containing the medium 64, for example , preferably granular carbon and coal dust, within the arrangement. That is, the liners 114 and 115 help to prevent the medium 64 from failing through the liners 112, 113 in or the interior of the filter 58 or outside the assembly of element 50 in total. The intermediate containment coatings 114, 115 are preferably an electrostatic felt. A usable material is described in detail later. The first end cover 120 is preferably a closed end cover. That is, the first end cover 120 does not include airflow openings therein, also generally, air is prevented from flowing through the first end cover 120 to the interior volume 58. In contrast, the second end cover 121 it is preferably an open end cover, having a central opening 125 therein (see FIGURE 6).

Preferably, the second element 54 operates to remove harmful fumes or odors from the air. E.L medium 64 is selected based on the types of gases or odors to be removed from the air. Preferably, the second element 54 acts as an absorbent or adsorbent. As used herein, the terms "absorbent" and "adsorbent" which mean the same should be considered. Normally, the second element 54 will be a chemical absorbent. In certain preferred systems, the second element 54 will be a macroparticle chemical absorbing medium. While a variety of intermediate structures can be used; and herein, in the preferred embodiment, the medium 64 includes activated carbon. Unat further description of the preferred example of means 64 of described below. Preferably, the first and second end covers 120, 121 are formed of a metal such as galvanized steel coupled material, with the liners 112, 113 and the middle 64 secured therein by impregnation with resins in the liquid state, for example . polyurethane or epoxy. In certain preferred constructions, an array is used to provide containment and packaging of the medium 64. In other words, if the selected medium 64 can be a loose or granulated macroparticle chemical absorbent, such as an activated carbon, the array provides an example in the present, the preferred system for ensuring that the loose macroparticle medium 64 remains in a firm, packed condition. Attention is directed to FIGURE 9. FIGURE 9 is a fragmented, enlarged cross-sectional view of the second element 5. FIGURE 9 describes a preferred packaging structure, generally numbered 140. In the example shown, the packaging structure 140 includes a plate, cover, or cover 141 and a compressible seal member 142. Preferably, the cover 141 is a cylindrical disc 141 constructed of a rigid, non-porous material, such as plastic. Preferably, the seal member 142 is a soft, compressible material having the same cylindrical shape as that of the second element 54. A material usable for the seal member 142 is rubber as well as neoprene, and is described in detail below. Still with reference in FIGURE 9, note that the inner liners 112 and 114 are preferably folded or folded or corrugated on the cover 141 in the region 145. Similarly, note that the outer liners 113, 115- fold, or fold , or corrugate over cub * ie.rta 141 in region 146. Las; Wavy or doubled portions 145, 146 are trapped, then, between the first end cover 120 and the, cover 141. To mount the second element 54, the second end cover 121 is preferably attached to the internal coatings 112, 114 and to the outer coatings 113, 115 by an epoxy or glue. Then, the medium 64, as a carbon particulate, is preferably filled between the inner liners 112, 114 and the outer liners 113, 115. The compression seal 142 is placed on the surface of the medium 64. The plate or cover 141 is positioned on the surface of the compression board 142. Then, preferably, the internal liners 112, 114 are folded over the cover 141 to form the region 145. The outer liners 113, 115 are preferably folded or folded over the cover 141 to form the region 146. It should be noted that the compression joint 142 operates to ensure firm packing of the medium 64. For example, if the activated carbon is used as the medium 64, the medium 64 can be established with time after the initial assembly. When the macroparticle carbon is established, the board 142 expands to , £. filling any void between the medium 64 and the cover 141. In use, the second element 54 is secured within the air purifier 20 with the opening 125 (FIGURE 6) circumscribed to the outlet conduit 28 (FIGURE 3). As a result of the use of proper sealing, by means of a variety of possible ways, for designs such as that shown in the FIGURES, the flow of; air is inhibited from reaching opening 125 without being filtered; through the middle 64. Attention is drawn to FIGURE 6. In FIGURE 6, a bottom view of the assembly of; element 50. Specifically, a preferred bottom plan view of the second element 54 is illustrated including an axial seal system. The axial seal system includes a seal member 130 circumscribed or around the outlet opening 125. Preferably, seal member 130 is a soft, compressible O-shaped ring 132. When the assembly of; element 50 is mounted within the housing 45 and the cover 47 is secured in place with clamps 32 (FIGURE 3) to provide the axial pressure, the seal member 130 provides a seal 136 (FIGURE 3) between the wall of the housing 45 and the second element 54.

It can be seen, then, that the particular preferred element assembly 50 illustrated comprises the first and second elements 52, 54 that flow in the opposite directions to each other. For example, the first element 52 operates to have the air flow from the inside to the outside, or a "reverse flow" system as shown by the arrows 147, FIGURE 3. This is in contrast to the second element 54, where the air flow is from the outside of the element 54 to the interior 58, or a "forward flow" system as shown by the arrows 148, FIGURE 3. This helps to keep the load more uniform, for example, if certain portions of the first element 52 begins to charge or occlude, it does not affect any particular portion of the second element 54 in its charge, attention is directed to FIGURE 10. In FIGURE 10 the first element 200 has been modified from the first element 52 described in FIGS. FIGURES 3-5 The first element 200 does not include a gasket member as the gasket member 106 to create an axial seal The first member 200 includes a structure of the adapter ring 202. The structure of the adapter ring 202 is oriented between the cladding inte 204 and the inlet conduit 218. A usable adapter annular structure is normally described in assigned U.S. Patent Application Serial No. 09 / 025,828, filed on February 19, 1993, incorporated by reference. In general, the structure of the adapter ring 202 comprises a circular member with legs 222 which engage or engage in the inner liner 204; an internal angled portion or surface 224; and a neck or end portion 206 As can be seen in FIGURE 10, the angled surface 224 extends between the legs 222 and the end portion 206. The end portion 206 may be a generally cylindrical member with a transverse, circular section that defines an inner radial surface 225. Still with reference to FIGURE 10, the first element 200 has a first end cover 210. As with the first end cover 95 of the embodiment of FIGURE 3, the first end cover 210 defines a flow opening. of air 212 through it. In contrast to the first end cover 95, the first end cover 210 in the embodiment of FIGURE 10 is constructed of a soft, compressible material such that the sealing portion 215 is compressed between and against the inlet conduit of the air flow 218. and the end portion 206 of the ring structure 202. A material usable for the first end cover 210 is a compressible polymeric material, such as polyurethane, more specifically, foamed polyurethane. A usable material L is normally described in US Patent No. 5,669,949 assigned to the end cover 3, incorporated herein by reference. As can be seen in FIGURE 10, the sealing portion 215 circumscribed in the opening 212. In this way, when the inlet conduit 218 is positioned within the opening 212, the sealing portion 215 is compressed between and against the conduit 218 and the end portion 206 to form a radial seal 220 between the; same. Other structural characteristics of the modality of FIGURE 10 are analogous to and are as they are; describe in the present with respect to the modalities; of FIGURES 1-9. Referring now to FIGURE 11, a fragmented cross-sectional view, of the first end cover 210 of the embodiment of FIGURE 10 is shown, in an uncompressed state. That is, the radial sealing portion 215 is shown when the filter element 200 is not installed in the air-reflecting housing and on the tube or conduit 218. Still referenced in FIGURE 11, the radial sealing portion 215 defines a unevenness of the inner diameters that increase of the surfaces for the connection with the air flow conduit 218.

Specifically, in the example shown in FIGURE 11, the radial seal portion 215 defines 3 stages, 235, 236, and 237. The dimension or amplitude in cross section of the stages that increments the additional stage is an upper portion 240 of the first end cover 210. As shown, later in step 237, there is a region 242 of decreased cross-sectional amplitude.

C. Housing 45 The attention is now directed to FIGURE 2. In FIGURE 2, a preferred housing 45 is illustrated. Preferably, the housing 45 is cylindrical with a cylindrical body 46 and a cover member 47. Referring now to FIGURE 3, the body of; housing 46 preferably includes a surrounding wall 150 and an axial bottom wall 152. The bottom wall 152 provides a closed end on the wall 150. The bottom wall 152 preferably includes an outlet conduit 28 extending and projecting therefrom, for providing communication of the air flow with the interior 58 of the second element 54. Opposed to the bottom wall 152, is an open end 154 of the housing 45. The end . - &, open 154 selectively opens and closes or covers and is discovered by cover member 47. Cover member 47 is preferably mounted on housing body 46 to be selectively secured thereon or completely removed therefrom. . Preferably, and with reference now to FIGURE 2, the cover member 47 is selectively mounted on the open end 154 by the clamps 32. The clamps 32 preferably comprise clamps over the center uniformly spaced around the outer periphery 156 of the open end of the clamp. housing body 154. The clamps on the center 32 are preferably spring metal clamps and may be those described in US Patent Application Serial No. 08 / 751,041, commonly assigned thereto, and incorporated herein by reference . The arrangement shown preferably uses 3-3 clamps, and in this embodiment, four clamps 32, evenly spaced over the periphery of the body 46 and the cover 47. Together, the clamps 32 provide a compressive force of at least 6.81 kg (15 lbs. .), and normally approximately 7.72-9.03 kg (17-20 lbs). This is to provide sufficient axial pressure in the element assembly 50 for t? provide firm air seals 110, 136 between the element assembly 50 and the housing 45. Referring now to FIGURE 3, the housing 45 preferably includes a structure for centering the element assembly 50. In the particular preferred embodiment illustrated, the housing 45 includes a plurality of projection members or spacers 160 on the axial extension of lower wall 152 of housing body 46. In general / spacers 160 preferably comprise straight columns 162 extending from lower wall 152. Each of the columns 162 preferably defines an oblique or tapered surface or portion 164, which helps provide a centered function. That is, due to the nature of the oblique or tapered portion 164, there is a leading edge that carries the element assembly 50 in the proper orientation within the housing 45. Preferably, those projecting outwardly from the columns 162 are the legs 165 The legs 165 support and support the element assembly 50 when it is oriented within the housing 45. Preferably, the height of the legs 165 is fixed for effect only: of the partial compression of the joint member 130. In the preferred arrangements, the The height of the legs 165 is such that the compression of the joint member 130 is not greater than 75% and normally approximately 50%. In other words, one of the advantages of the legs 165 is that they prevent the fixed compression in the seal member 130 and ensure that the upper seal member 106 has sufficient compression to form the seal 110., in the axial seal arrangement. Preferably, the height of the legs 165, that is, the distance of the bottom 152 to the surface of each leg 165, is preferably: about 0.51 cm (0.2 inches), and in one example, 0.48 cm (0.19 inches). For a joint member 130 having a cross-sectional thickness of about 0.96 cm (3/8 inch), a height of: the legs 165 of about 0.48 cm (0.19 inches) of load at a compression of the joint member 130 of; approximately 50%. Preferably, the housing 45 includes a structure for mounting the housing 45 to the support structure. The support structure may include a variety of arrangements, such as a plate. In FIGURE 8, an example of the preferred mounting structure is shown. Preferably, the mounting structure includes a bolt circle with a plurality of mounting locations 170. Mounting locations 170 preferably include flanges or flange nuts 172 with internal threads to accept threaded screws therein. The nuts 172 are suitable for joining the housing 45 through the such as welding. Preferably, the locations d 'assembly 170 are uniformly spaced over the periphery 174 of the bottom wall 152. In the preferred embodiment shown in FIGURE 8, there are four mounting locations 170 spaced approximately 90 ° apart.

D. Methods to Determine Filter and Service Replacement. The preferred air purifier 20 includes a way to communicate that the element assembly 50 requires service or change. Attention is drawn to FIGURE 7. In FIGURE 7, a preferred system for indicating when the change is needed and for indicating whether or not the filter element assembly 50 is installed in the housing or is not generally shown with the numeral 180. In FIGURE 7, the system 180 includes a pressure cover 182 preferably upstream of the first filter element 52. A second pressure tap 184 is preferably provided just downstream of the first element 52, but upstream of the second element 54 A third pressure port 186 is preferably provided downstream of the second element 54. In general, the pressure ports 182, 184, 186 preferably include openings in the housing 45, approximately 1/32 inch, National tube with a brass hose armed with barbs that adjusts to fit the hoses 194, 195, 196, 197. Preferably, a differential switch of; Pressure 190 is oriented between the first pressure port 182 and the second pressure port 184. The pressure differential switch 190 indicates the pressure drop in the first element 52. Preferably, between the second pressure port 184 and the third port of pressure 186 is a second differential pressure switch 192. The second differential pressure switch 192 indicates the pressure drop in the second element 54. Usable switches may be part of the No. MPL-502 commercially available from Micro-Pneurnatics Logic Inc of Fort Lauderdale, Florida. The reading of the differential pressure switch 190 indicates when the filter assembly 5C needs to be replaced. Specifically, the pressure drop in the particulate filter 52 will increase as the medium 60 is charged. Once the pressure drop exceeds a fixed value in switch 190, the switch will close indicating the need to change element assembly 50. Pressure differential switch 192 will indicate the presence or absence of filter assembly 50 and / or an obstacle to flow through the entire system. For example, if the inlet hose 22 c the outlet hose 30 (FIGURE 1) are blocked, or if the ventilation chamber 16 stops work, this will be indicated by the second pressure differential switch 192. Specifically, the fall of pressure in the second element 54 will be before a minimum value if the filter assembly 50 is present, and if there is air flow. The pressure switch 192 will close if the filter assembly 50 is installed, and if there is air flow through the system. When it is time to change the element assembly 50, for example, when the pressure differential switch 190 indicates that it is time to change due to the charged particulate filter element 52, the arrangement described herein lends itself to a convenient and rapid change. Preferably, the change is carried out every one or two weeks, with an estimated 1.02 kg (2.25 pounds) of macroparticle captured in the first element 52. Preferably, the life of the noxious gas captured by the second element 54 exceeds the life of the element of filter; macroparticle 52. To change the element assembly 50, the following steps are preferably performed. The cover 47 is removed from the housing 45. Preferably, this is by decoupling the clamps 32. When the cover 47 is decoupled from the body 46, the seals 110, 136 between the element assembly 50 and the housing 45 break. By removing the cover 47, the first end cover 95 of the first element 52 is exposed. The person making the change then grasps the secured handle 75 to the element assembly 50. The handle 75 is rotated out of the end cover 95 and the element assembly 50 is lifted through the open end 154. First, the first element 52 it passes through the open end 154, followed by the second element 54. The assembly of worn element 50 above is discarded. In some cases, it may be desirable to recycle certain macroparticles captured in the first element 52. The particulate material collected within the first element 52 remains within the interior of the first element 52 and does not have a í. ? i? & .Mi * _y $ > yy »"% y ^^ ia c ^ __________________ opportunity or access to a hole to fall outside the. interior 56. A second, different, new filter assembly 50 is then provided. The person takes the seal 75 from the new element assembly 50 and places it inside the housing 45. Specifically, the second member 54 passes through the open end 154, followed by the first member 52. The spacers 160 help center the assembly element 50 centering the second end cover 121 on the bottom wall 152 of the housing 45. The air flow opening 125 in the second end cover 121 is placed in fluid air communication with the outlet conduit 28. The cover 47 is then oriented to close the open end 154, when placed on the end of the element assembly 50. The inlet conduit 24 is placed in fluid air communication in with the air flow opening 100 of the first end cover 95. The clamps 32 then they are secured to secure the cover 47 to the body 46. When the clamps are closed or adjusted over the center, the axial pressure is applied between the element assembly 50 and the housing. to 45. The axial pressure causes a firm air seal 110 between the gasket member 106 and the cover 47, and creates the seal 136 between the gasket member 130 and the bottom wall 152. In the preferred systems, the total time for make the change of element assembly 50 is; less than five minutes, and preferably less than three; minutes E. Sample Materials The following section provides examples of the normal preferred materials, and in certain cases stop the arrangements herein. It is understood, of course, that alternative materials can be used if they are appropriate. The housing 45 is preferably constructed of metal, for example steel, having a thickness of 1.12 millimeters (0.044 inches). The end covers 95, 96 and 120, 121 can include metal, for example galvanized steel, of 1.12 millimeters (0.044 inches in thickness) O-ring 107 and 132 and the seal member 142 can be constructed of rubber, for example Neoprene sponge rubber / EPDM / SBR This has a compression of approximately 25% deviation at 2-5 psi, and a hardness of approximately 30-45 cutting.Having a density of 2.27-318 kg (5-7 lbs) ) / cu. ft., and a tension force of 80 psi Operating within a temperature range of -21.11-121.11 ° C (-70 ° to + 250 ° F) The medium 60 may comprise a folded medium, or alternatively, a lower medium If the oil medium is used, in general, a medium of cellulose fiber or medium comprises cellulose fibers and synthetic fibers which can be used.The medium can be treated, more or less? , with oiling as described in U.S. Patent No. 5,423,892 incorporated herein by reference. For example, the medium can be treated with extended oolitetrofluoroethylene (PTFE). Also, as explained in the 'Patent Nort American No. 5,423,892, incorporated herein by reference, the efficiency of the barrier medium may be modified as paper or cellulose in a.1"runes" or by applying to a surface of the medium a deposit of relatively fine fibers norm.alm It is less than five microns and in many cases fibers (average) according to the size of the submicron. A preferred means 60 includes a flame retardant air filter means. This medium has the following properties: Frazier permeability of approximately l mt. (50 ft) / m minimum, and one value expected from 4.80-5.40 mt. (16-18 ft.) / M. Force for drying interruption of at least 3.63 kg (8 pounds), and expected values of approximately 4.09-6.36 kg (9-14 pounds). Force to interrupt moisture of at least 2.04 kg (4.5 pounds), and expected values of approximately 2.27-8.1 '' kg (5-18 pounds). Base weight not greater than 36.32 (80 lbs.) / 0.28 mt " (3,000 ft2), and expected values of approximately 33.60-35.87 kg (74-79 lbs.) / 0.28 mt2 (3,000 ft). Bursting force of humidity of at least psi, and expected values of: approximately 18 psi. Pore size not greater than about 55 micrometers, and normally of; approximately 48-53 micrometers Corrugation of at least 0.51 millimeters; (0.020 inches), and normally from 'approximately 0.53 millimeters (0.021 inches).

Thickness of at least 0.30 millimeters .0.012 inches), and normally of > approximately 0.33-0.38 millimeters (0.013-0.015 inches). Dry infusion of at least 25 J / sq. and normally of at least 30 J / sq. Dust load of at least 14.9 g / sq. mt. (ft.) at 2.40 meters (8 feet) per minute, and usually approximately (16.7 g / sq. mt. (ft.) A gurley stiffness of at least 2, OOC mg., and usually at least 2,400 mg Flame retardant no greater than 12.70 cm (five inches) maximum burn length and usually approximately 5.08-10.16 cm (2-4 inches) Medium 64 is preferably an activated carbon impregnated with potassium iodide, To absorb the formaldehyde gases If only the absorption of the odor is needed (and the formaldehyde gas absorption is not needed), then the need for the activated carbon is not impregnated with potassium iodide.

The average 64 preferably has the following specifications: Activity level of CCl4, according to ASTM D-3467 of at least 55% (base). Moisture content according to ASTM D-2867 no greater than about 15-22%. Particle size according to ASTM D-2862 of 6 × 12 North American mesh. Medium 64 preferably has a hardness according to ASTM D-3892 of 97. Having a bulk density according to ASTM D-2854 of 0.60. g / cm3. Having a volume of ash according to ASTM D-2866 of 3% (base). Having a surface area, BET N2 of 1150 prVg (base). The medium 64 is usually of coarse, granular particles, approximately 1.52 millimeters (1/16 inch) in average diameter. In operation, the medium 64 will remove the formaldehyde gas, such that the downstream of the air cleaner 20 will be less than 0.1 parts per million formaldehyde in the air. A preferred activated carbon is commercially available from Barnebey & Sutcliffe of Columbus, Ohio, under the trademark FormaSorb®. The internal and external coatings 114, 115 containing the medium can normally be an electrostatic felt without needles mixed fibers (50fe polypropylene and 50% odacrylic) with the following properties: Fomblin Efficacy: 76-94% average without the value below of 71 or above 99, tested at 3.15 meters (10.5 feet) per minute of air flow; 0.3-0.4 microns of particulates. Permeability: 84.90-142.80 meters (283-476 feet) per minute (86-145 meters per minute), Thickness at 0.5 psi: 0.91-1.55 mm (0.036-0.061 inches) Base weight: 78-122 grams per square meter (48-75 pounds per 3,000 square feet) F. An Example Structure In the following paragraphs, a specific preferred example of an air purifier assembly is described. It is understood, of course, that alternative structures and dimensions can be used. In operation, the air purifier 20 will remove an estimated 1.02 kg (2.25 pounds) of particulate after operating for approximately one or two weeks. The minimum air flow speed will be approximately 30 ft. A, and the maximum air flow rate through the purifier 20 will be approximately 85 ft.Am. .to. * • * ,,.

The axial length between the end tip of the inlet duct 24 and the outlet duct 28 will be at least about 50.80 cm (20 inches), and will normally be about 63.50 cm (25 inches). The diameter of the inlet conduit 24 will be at least about 2.54 cm (1 inch), not more than about 10.16 cm (4 inches), and usually about 4.45 cm (1.75 inches). The diameter of the housing body 46 will be at least about 30.48 cm (12 inches), not greater than; approximately 60.96 cm (24 inches), and normally: approximately 40.64 cm (16 inches). The axial length of the outlet duct 28 is at least; about 2.54 cm (1 inch), no more than about 10.16 cm (4 inches), and usually about 4.83 cm (1.9 inches). The outlet conduit 28 may have a diameter of at least about 2.54 cm (1 inch), no more than about 10.16 cm (4 inches), and typically of: about 3.18 cm (1.25 inches). The element assembly 50 will have an overall axial length of at least about 30.48 CK (12 inches), no larger than approximately 63.50 cm (25 inches), and normally approximately 49.02 cir (19 inches). The axial length of the first element .y¿¿?? r .. .. aáta «fc» a a? £ _. 52 will be at least about 25.40 cm (10 inches), not more than about 50.80 cm (20 inches), and normally about 41.15 cm (16.2 inches). The axial length of the second element 54 will be at least about 2.54 cm (1 inch), not more than about 25.40 cm (10 inches), and usually about 7.87 cm (3.1 inches). The internal diameter of the first and second elements 52, 54 will be at least about 12.70 cm (5 inches), not more than about 30.48 c (12 inches), and usually about 24.77 cm (9.75 inches). The radial thickness of the intermediate structures 60 and 64 will normally be at least about 2.54 cm (1 inch), not more than about 10.16 cm (4 inches), and typically about 'about 5.08 cm (2 inches). The outside diameter of element assembly 50 will be at least about 17.78 cm (7 inches), not more than about 50.80 cm (20 inches), and usually about 34.93 (13.75 inches). The diameter of the opening 100 in the first end cover 120 will be at least about 3.18 cm (1.25 inches), not more than about 10.80 cm (4.25 inches), and usually about 5.08 cm (2.0 inches). The diameter of the outlet opening 125 in the second end cover 121 will be at least about 3.18 cm (1.25 inches), not more than about 10.80 cm (4.25 inches), and typically about 5.08 cm (2.0 inches). The internal diameter of the gasket member 100 would be at least about 27.94 cm and 3.30 millimeters (11 and 1/8 inches), not more than about 34.29 cm (13.5 inches), and usually about 29.85 cm (11.75 inches). The gasket 100 will typically have at least a radial thickness of about 6.35 millimeters (0.25 inches), not more than about 3.18 cm (1.25 inches), and typically about 1.91 cm (0.75 inches) .. Having a cross-sectional thickness of at least about 0.64 millimeters (0.25 inches), no greater than about 1.27 cm (0.5 inches), and normally about 9.63 millimeters (3/8 inches), The joint member 130 will have dimensions; similar to those of the gasket member 100. The spacers 160 will normally have: projections of at least 0.25 cm (0A inches), nc > greater than about 5.08 cm (2 inches), and typically about 0.48 cm (.3 / 16 inches) away from the bottom wall 152.

The above specification, examples and data provide a complete description of the development and use of the invention. Many embodiments of the invention may be made without departing from the spirit / scope of the invention.

It is noted that in relation to this date, the best method known by the applicant to carry out the aforementioned invention, is the conventional one for the manufacture of the objects or products to which it refers. Having described the invention as above, the contents of the following are claimed as properties:

Claims (19)

1. A filter element assembly characterized in that it comprises: (a) a first intermediate structure; the first intermediate structure has the first and second opposite end covers with a first medium extending therebetween, the first means and the first and second covers define an interior of the open filter; (i) the first means comprises a folded medium; (ii) the first end cover has an air flow opening in fluid air communication with the interior of the filter open said first; and (A) a joint member in the first end cover of the first intermediate structure; circumscribed to the first air flow aperture of the extreme cube of the first intermediate structure; (iii) the second end cover that closes the air flow through it; (iv) the first intermediate structure provides a path of air flow from the interior of the open filter through the first medium; Y (b) a second intermediate structure; this second intermediate structure has the first and second ends having a second medium extending therebetween, the second means and the first and second ends define an interior of the open filter; (i) the second means comprises an activated carbon; (ii) the second intermediate structure is secured to and stacked in alignment axiaJ. with the first intermediate structure; (iii) the first end of the second intermediate structure is closed for the flow of air therethrough; and (iv) the second end of the second intermediate structure includes an air flow opening in communication with the interior of the open filter of the second intermediate structure; the second end of the second means is at one end of the mounting of the filter element opposite the first end cover of the first intermediate structure ^ (A) a joint member in the second end cover of the second intermediate structure circumscribed to, the second airflow opening 'of the end cover of the second, intermediate structure; (v) the second intermediate structure provides a path of the air flow through the second medium inside the open filter; and (vi) the path of the air flow progresses through the first intermediate structure and then through the second intermediate structure.

2. A filter element assembly according to claim 1, characterized in that: (a) the second intermediate structure includes a first end cover closed at the first end; and a second cover , '. extreme that has an airflow opening at the second end.

3. A filter element assembly according to claim 2, characterized in that: (a) the first intermediate structure is secured to the second intermediate structure by spot welds.

4. A filter element assembly according to any of claims 2 and 3, characterized in that: (a) the first intermediate structure is cylindrical with an external coating and an internal coating extending between the first and second end covers of the first structure; intermediate; and (b) the second intermediate structure is cylindrical with an outer coating and an inner liner extending between the first and second end covers of the second intermediate structure. any of claims 2-4, characterized in that: .., ^. and " (a) the first end cover of the second intermediate structure is adjacent to the second end cover of the first intermediate structure. 6. A filter element assembly according to any of claims 1-5, characterized in that: (a) the seal member in the first end cover of the first intermediate structure comprises an O-shaped ring. 7. A filter element assembly according to any of claims 2-6. characterized in that: (a) a seal member in the second end cover of the second intermediate structure comprises a ring in the form of: 0. 8. A filter element assembly according to any of claims 1-7., characterized in that: (a) the first intermediate structure comprises folded paper. 9. An air purifier having a filter element assembly according to any of claims 1-9, characterized in that: (a) a housing having an interior, an inlet duct, and an outlet duct; and (b) the filter element assembly that is removable and replaceable within the housing; (i) the air flow opening of the first end cover of the first intermediate structure provides for fluid communication of air between the inlet duct of the housing and the open interior of the first intermediate structure; (ii) the second end opening of the second intermediate structure provides a fluid communication of air between the open interior of the second intermediate structure and the outlet conduit of the housing. An air purifier according to claim 9, characterized in that: (a) a housing includes a removable cover that provides access to the interior of the housing and to the filter element assembly.- 11. An air purifier in accordance with claim 9 and 10, characterized in that: (a) the housing includes a plurality of clamps to selectively secure the cover to the housing. 12. An air purifier according to any of claims 9-11, characterized in that: (a) the housing includes a plurality of: spacers along an interior wall of the housing. 13. An air purifier according to claim 12, characterized in that (a) the second intermediate structure is centered between the spacers. An air purifier according to any of claims 9-13, characterized in that: (a) the filter element assembly includes a handle operably secured thereto for orienting and removing the filter element assembly within the housing. 1

5. An air purifier according to any of claims 9-14, characterized in that: (a) the filter element assembly includes a sealing arrangement to provide a seal between the filter element assembly and the housing. 1

6. An air purifier according to claim 15, characterized in that: (a) the sealing arrangement includes a first joint member in the first end cover of the first intermediate structure 10 circumscribed in the inlet conduit; (i) the seal member forms a seal between the first intermediate structure and the cover of the housing, when the cover of the housing is in 15 closed orientation. (a) the sealing arrangement includes a second board member at the second end of > the second intermediate structure circumscribed in the outlet conduit; 20 (i) the second seal member of the filter element forms a seal between the second intermediate structure and the housing. ^^^ - 1

7. An air purifier according to any of claims 9-16, characterized in that: (a) a vent chamber assembly directs the flow of air through the inlet conduit, inside the the first intermediate structure, through the first intermediate structure, through the second intermediate structure, inside the second intermediate structure, and out through the outlet conduit. 1

8. An air purifier according to any of claims 9-17, characterized in that it includes: (a) a first current pressure tap: above the first intermediate structure; a second current pressure tap: downstream of the first intermediate structure and upstream of the second structure; intermediate; a third current pressure tap below the second int rmedia structure; (b) a first differential pressure switch is connected to the first second pressure sockets to indicate a pressure drop in the first intermediate structure, and (c) a second differential pressure switch connects to the second and third pressure sockets for indicate a fall of: pressure in the second intermediate structure. A method for repairing an air purifier according to claim 11, characterized in that it comprises the steps of: (a) removing the housing cover to expose an opening to the interior of the housing, the filter element assembly is oriented inside the housing, (b) grasping a handle on the filter element assembly; (c) lifting the filter element assembly through the opening with the handle; the first filter element passes first through the opening; and the second filter element passes through the opening after the first filter element.