Abstract:
The invention relates to a filter arrangement comprising a plate-shaped filter holder ( 12 ) provided with at least one stem-type protruberance ( 13 ) having an opening ( 11 ) said filter holder ( 12 ) being used to receive a filter element ( 14 ) in a sealed manner for each protuberance on the raw gas side of the filter holder. In order to ensure that the filter is changed easily with sufficient filtering safety, each filter element ( 14 ) is provided with an adapter collar ( 15 ) comprising at least one limb ( 15 B;  15 D) parallel to the protruberances. Said limb can be placed, from the raw gas side, inside or over the protruberance. A sealing arrangement ( 16 ) provided comprises sealing elements ( 16 A,  16 B) which are parallel to both the plates and to the protruberances and are used for the at least partial join between the protruberance and the adapter collar.

Description:
This application claims priority to and the benefit of the filing date of International Application No. PCT/EP2008/003979, filed May 16, 2008, which application claims priority to and the benefit of the filing date of German Application No. 20 2007 004475.5, filed Mar. 23, 2007, both of which are hereby incorporated by reference into the specification of this application. 
     FIELD OF THE INVENTION 
     The invention relates to filter arrangements and, more particularly, to filter arrangements including a plate-shaped filter holder presenting at least one neck-shaped protuberance while leaving clear, in each case, an opening that is associated with a filter cartridge. 
     TECHNOLOGICAL BACKGROUND 
     Filter elements that can be assembled or installed as construction units in a filter arrangement, in a number corresponding to the need, are usually screwed in a sealing manner on a plate-shaped filter holder, such as, for example, according to DE 203 12 074 U1, FIG. 1 which is incorporated by reference as background material for showing the same. 
     A typical application of generic filter arrangements consists of the so-called vacuum conveyance installations, as known from DE 203 12 074 U1, which presents a collection container for transported material that is aspired by a vacuum. The negative pressure of a vacuum pump is applied to the collection container, and the transported material is deposited by gravity on the bottom of the collection container, while the suction air leaves the collection container at the top through the opening of the plate-shaped filter holder. Already for the protection of the vacuum pump, and for the complete use the transported material, only the suction air is allowed to pass to the vacuum pump through the filter elements that close the openings, and not the transported material or dust components. Such filters, which can be made from ceramic, flow material or other filter surface material, present as a rule a cartridge shape (hanging cartridge). If the performance of a filter cartridge worsens or if the filter cartridge contains cracks and has to be replaced, in spite of regular counter-pressure cleaning, the cost is similarly high. 
     In the case of filter hoses in fine dust filters, the raw gas side hose openings are usually clamped between conic rings, and the external ring is screwed to the plate-shaped filter holder that is provided with openings (DE 41 34 679 A1) which is incorporated by reference as background material for showing the same. The external holder ring can also be welded to the perforation margin or the filter holder can be designed as one piece with the filter holder (DE 40 31 375 A1) which is incorporated by reference as background material for showing the same. The filter hoses can be replaced by removing an inner cone on their gas inlet opening, where the hose opening can present a bead-like clamping margin (DE 816 852 C) which is incorporated by reference as background material for showing the same. 
     Filter arrangements with adaption collars connected to the filter elements are also known. Thus DE 203 12 074 U1 presents a two-part adaption collar (FIGS. 1 and 2), which is screwed by means of a flange-like protruding attachment sheath with external threading and with the interposition of a ring seal with a flat, perforated filter holder plate, so that the attachment sheath and the adaption collar clamp the flat filter holder on opposite sides between themselves. The handling of such a filter arrangements during the filter replacement requires a certain degree of skill so that the desired lasting seal can also be achieved. Instead of a screw connection, DE 90 14 198 U1 which is incorporated by reference as background material for showing the same provides fixation pins on the pure gas side acting on an adapter flange of the filter element. For their fixation, it is necessary to weld an annular attachment collar for the fixation pins with considerable radial separation from the perforation of the flat filter holder plate to the latter. It is only in this way that the cartridge-shaped filter element, which is provided with its adapter flange forming a single piece, can be slid from the pure gas side, with interposition of a sealing collar, into the attachment collar, and put on the pure gas side on the plate-shaped filter holder. The insertion of the filter cartridge from the top is an impediment in many applications, and disadvantageous for the sealing function because of the raw gas pressure applied from below. 
     Generic filter arrangements, which are the starting point of the invention, present at least one neck-shaped protuberance of the plate-shaped filter holder. They are known from U.S. Pat. No. 3,997,305, among others, which is incorporated by reference as background material for showing the same. According to the latter patent, a spreading basket with a filter hose that is placed around its opening over the neck-shaped protuberance and pulled in a sealing manner close to the external margin of the neck-shaped protuberance by an external clamping ring. To receive venturi-like nozzles in the interior of the hose, a piece of pipe with stepped diameter is slid into the neck-shaped protuberance, and welded firmly to it. An additional generic hose filter arrangement is known from DE 203 12 074 U1, FIG. 4B. In both known applications of plate-shaped filter holders with neck-shaped protuberances forming an opening, which are the starting point of the invention, no special sealing arrangements are used. Rather, the purpose is to have the filter hose be applied in a sealing manner on the external circumference of the neck-shaped protuberance under the radial pressure of a clamping means. According to DE 203 12 074 U1, the neck-shaped protuberance serves in addition as a welding collar for the lasting attachment of a non-replaceable filter cartridge with support function for the filter hose. The generic filter arrangements are in fact easy to manufacture and flow enhancing; however, the clamp attachment of the filter hose that has been put over is found to be time consuming. In addition, such filter arrangements have been unsuitable so far for finished filter elements consisting of a filter cartridge with prefabricated adaption collar. 
     DESCRIPTION OF THE INVENTION 
     The invention is based on the problem of providing a simple design for filter replacement in a filter arrangement of the generic type with sufficient filtering safety. 
     To solve the problem, provided is a filter arrangement having wherein each filter element is provided with an adapter collar, and the adapter collar presents at least one first limb which is parallel to the protuberance with respect to the protuberance, where this limb can be inserted from the raw gas side or via the protuberance, and in that a sealing arrangement is provided, which presents sealing elements that are parallel to both the plate and also the protuberance, for the at least partial insertion between the areas of the protuberance and areas of the adapter collar. 
     In this way, the adapter collar can be inserted radially in a sealing manner from the raw gas side into the neck-shaped protuberance of the plate-shaped filter holder, or it can be put over the latter, until an area of the adapter collar, which is parallel to the plate, is applied radially outside of the protuberance of the filter holder in a sealing manner against the raw gas side of the filter holder. This can occur in such a way that the sealing arrangement is already applied against the adapter collar, and thus slid together with the adapter collar in or over the neck-shaped protuberance of the plate-shaped filter holder. 
     The frictional resistance of the sealing arrangement on the neck-shaped protuberance may already be sufficient to secure the filter element on the plate-shaped filter holder, where suction pressure applied to the filter element reinforces the sealing effect. According to another aspect of the invention, a quick release safety latch can be provided on the adapter collar, which can be applied, for example, by simple flipping over of a securing clip, on the backside of the plate-shaped filter holder, in such a way that the adapter collar is held as a result in that target position. Even if this quick release safety latch fails, for example, if it opens, it can ensure that the filter element is prevented from sliding completely out of the sealing area that is parallel to the protuberance, and thus a safety sealing effect is maintained. 
     Another aspect relates to hygiene, which is ensured by the fact that the sealing element that is parallel to the plate protects the connection and sealing arrangement from damaging cavity and lump formation. 
     The above mentioned components as well as the components which are claimed and described in the embodiment examples, and to be used according to the invention, are not subject to any special exception conditions with regard to their size, shape, material selection and technical design, so that the selection criteria known in the application field can be used without restriction. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Additional details, characteristics, and advantages of the object of the invention can be obtained from the dependent claims as well as from the description given below of the corresponding drawing and table, in which embodiment examples of a filter arrangement are represented for illustration. 
       In the drawing, 
         FIG. 1  shows an axial cross section through a filter arrangement according to the invention; 
         FIG. 2  shows an alternative embodiment of the filter arrangement according to  FIG. 1  in two different versions; 
         FIG. 3  shows a top view from above of the filter arrangement according to  FIG. 1 ; and 
         FIGS. 4A-C  show an axial cross section—in cutouts—of alternative filter arrangements of different design of the neck-shaped protuberance and the seal. 
     
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
     Referring now to the drawings wherein the showings are for the purpose of illustrating preferred and alternative embodiments of the invention only and not for the purpose of limiting same,  FIG. 1  shows a plate-shaped filter holder  12  which can be of any size, and which has at least one opening  11  whose margin is formed by a neck-shaped protuberance  13  which, in the represented embodiment example, forms a substantially cylindrical, molded collar that extends upward. Other collar shapes as well as multipart designs of the protuberance and the filter holder are possible, within the scope of the invention, to an almost limitless extent; for example, they may be welded to each other. 
     A filter element  14  of appropriate material type and shape is connected in a sealing manner with an adapter collar  15  on its opening margin. In the represented embodiment example, the adapter collar  15  presents two limbs, in a cross sectional view, namely a limb  15 A parallel to the plate, and a limb  15 B parallel to the protuberance. Both limbs are, in the represented embodiment example, areas of a single-piece component. It is also possible to use adapter collars assembled from several elements, such as limbs that are at first separated. The cross section of the limb  15 B that is parallel to the protuberance is sufficiently smaller on its external side than the clear cross section of the protuberance  13  of the filter holder  12 , so that the adapter collar  15  can be inserted with peripheral clearance into the protuberance  13 . The interstice is bridged by a sealing arrangement  16 , which presents a sealing element  16 A parallel to the plate, and a sealing element  16 B parallel to the protuberance. In the represented embodiment example, the sealing arrangement  16  forms a single piece. It has continuous peripheral sealing lips  16 A′ on its limb  16 A parallel to the plates, on the side of the adapter collar  15 , and continuous peripheral sealing lips  16 B′, in the area of the radial external side of the limb  16 B parallel to the protuberance, which are applied in a sealing manner in the inner circumference of the protuberance  13  in the state of use. One or more circumferential or shorter bead-like protrusions  16 C of the sealing arrangement  16  can correspond to appropriate recesses on the periphery of the limb  15 B, which is parallel to the protuberance, of the adapter collar  15 , so that the sealing arrangement can be inserted into a prescribed position on the adapted collar  15 , before the filter element  14  is inserted with its adapter collar  15  into the recess  13 . 
     A quick release safety latch  17  in the form of a springy securing clip  17 A can be suspended in such a way that it can swivel in appropriate recesses—such as perforations—of the limb  15 B, which is parallel to the protuberance, of the adapter collar  15 , and shaped in such a way that the securing clip  17 A is applied on the backside of the filter holder  12  in such a way that the filter element  14  is applied securely as a result on the filter holder  12  under operating conditions. Even if this quick release safety latch fails, for example, if it opens, it can ensure that the filter element is prevented from sliding completely out of the sealing area parallel to the protuberance, and thus at least a radially acting safety sealing effect is maintained. This can be achieved, for example, by appropriate dimensioning of the suspension area of the securing clip. 
     According to another embodiment of the invention, which by itself is also of inventive significance, a storage or fluid treatment element—not shown in the drawing—for cleaning purposes, for example, can be associated with the adapter collar ( 15 ) on the backside of the filter holder, which is turned away from the filter element. This element can be arranged after the outlet opening of the limb ( 15 B), which is parallel to the protuberance, particularly with axial and/or radial separation leaving at least one passage for liquid, and it can be supported on the adapter collar ( 15 ), the filter holder ( 12 ) and/or on a safety latch ( 15 C,  17 ). As holder element for the storage or liquid treatment element, a spacer with double function can be used, which can also fix the closed position of the safety latch. The holder element can be designed as a bayonet closure that works in collaboration with the safety latch. 
     In the embodiment example according to  FIG. 2 , a screw locking device is used instead of a securing clip, where in the left half of the figure a screw nut  15 C is applied against a crimping  13 A of the protuberance  13 , while in the right half of the figure, the screw nut  15 C′ is designed as a coupling nut, and supported on the backside of the filter holder  12 . For the rest, the structure and function of this embodiment example correspond to those according to  FIG. 1 . 
     The embodiments according to  FIGS. 4A to 4C  illustrate additional design possibilities for a protuberance  13 , an adapter collar  15 , and a sealing arrangement  16 . All the embodiment examples  4 A to  4 C share the fact that the protuberance  13  is directed inward in that case, i.e. toward the filter element  14 . 
     According to  FIG. 4A , the adapter collar  15  is designed, as in the embodiment example according to  FIGS. 1-3 , with two limbs  15 A/ 15 B and made as a single piece, where the limb  15 A parallel to the plates is braced against the front edge of the protuberance  13  with the interposition of the one-piece, two-limbed sealing arrangement  16 . A grooving and ribbing  18 A/ 18 B between the limbs of the sealing arrangement and of the adapter collar, which limbs are parallel to the plates, improves the axial sealing effect in spite of the small overall dimension. 
     In the embodiment example according to  FIG. 4B , the adapter collar  15  presents a sealing limb  15 D, which is parallel to the protuberance, and which posses a limb surface  15 D′ parallel to the protuberance and a limb surface  15 D″ parallel to the plate. The sealing limb  15 D is shifted over the protuberance  13  of the filter holder  12  from below, where the radial external side of the protuberance  13 , and the adjacent surface area, which is parallel to the plate, on the bottom side of the filter holder  12 , serve as sealing surfaces  13 ′ and  13 ″. The protuberance  13  thus engages advantageously in a circumferential groove  15 E provided on the adapter collar  15 . The sealing arrangement  16  is, for the rest, designed in the same functional way as the embodiment example according to  FIGS. 1-3 , as one can easily see in  FIG. 4B . 
     In the embodiment example according to  FIG. 4C , the structure of the adapter collar  15  corresponds substantially to the adapter collar  15  according to  FIG. 4B , where, however, both limbs  15 B and  15 D, which are parallel to the protuberance, of the adapter collar  15  have sealing functions. In this embodiment example, the sealing arrangement  16  is in two parts, and it consists of a sealing element  16 B parallel to the protuberance, which extends between the radial external surface of the radially internal limb  15 B, which is parallel to the protuberance, of the adapter collar  15 , on the one hand, and the radial inner surface  13 ″ of the protuberance  13 , on the other hand. A sealing element  16 A parallel to the plates is designed and arranged separately and similarly to an O-ring seal. For this purpose, the opening margin of the limb  15 D, which is parallel to the protuberance, of the adapter collar  15  presents an appropriate reception recess  15 F. 
     An additional aspect is hygiene, which is ensured by the fact that the sealing element parallel to the plates, particularly on its radial external side, protects the connecting and sealing arrangement against damaging cavity and lump formation. Overall, the invention achieves an arrangement in the sealing area between the filter holder and the filter element, which presents few or no slots and offsets, so that it is possible advantageously to take into account above all the hygienic viewpoints which play a special role, for example, with pharmaceutical products. 
     Further, as is discussed in greater detail above, the invention of this application relates to a filter arrangement comprising at least one plate-shaped filter holder ( 12 ) presenting at least one neck-shaped protuberance ( 13 ) with an opening ( 11 ), for the sealing reception of one filter element ( 14 ) per protuberance, from the raw gas side of the filter holder, wherein each filter element ( 14 ) is provided with an adapter collar ( 15 ), and the adapter collar ( 15 ) presents at least one limb ( 15 B;  15 D) which is parallel to the protuberance, with respect to the protuberance ( 13 ), where this limb can be inserted from the raw gas side in or over the protuberance ( 13 ), and in that a sealing arrangement ( 16 ) is provided, which presents sealing elements ( 16 A,  16 B) that are parallel both to the plate and to the protuberance, for the at least partial insertion between the protuberance ( 13 ) and the adapter collar ( 15 ). 
     According to yet another embodiment, the adapter collar ( 15 ) presents a limb ( 15 B) that is parallel to the protuberance and protrudes radially over the limb ( 15 A) that is parallel to the plate. 
     According to a further embodiment, the filter arrangement can further include a safety latch, such as a quick release safety latch ( 17 ), for the adapter collar ( 15 ) with respect to the filter holder ( 12 ) is provided. 
     According to yet a further embodiment, the quick release safety latch ( 17 ) engages on the filter holder on the side of the filter holder ( 12 ) facing the filter element ( 14 ). 
     According to another embodiment, the quick release safety latch ( 17 ) presents a swiveling securing clip ( 17 A). 
     According to a further embodiment, when the securing clips ( 17 A) are not locked, the quick release safety latch ( 17 ) prevents the adapter collar ( 15 ) of the filter element from sliding completely out of the sealing area that is parallel to the protuberance. 
     According to yet a further embodiment, the neck-shaped protuberance ( 13 ) is molded on the opening margin of the filter holder ( 12 ) as collar. 
     According to yet another embodiment, between the protuberance ( 13 ) of the filter holder ( 12 ), and a limb ( 15 B or  15 D) of the adapter collar ( 15 ), which is parallel to the protuberance, a gap remains, which is bridged by a part of the sealing arrangement ( 16 ). 
     According to yet a another embodiment, at least one continuous circumferential sealing lip ( 16 B′) of the sealing arrangement ( 16 ), on the sealing side facing the protuberance ( 13 ) is provided. 
     According to yet a further embodiment, at least one continuous circumferential sealing lip ( 16 A′) , on the sealing side facing the adapter collar ( 15 ). 
     According to yet a further embodiment, a holding means for holding the sealing arrangement ( 16 ) on the adapter collar ( 15 ) is provided for the joint sliding of the adapter collar including the sealing arrangement in or over the protuberance ( 13 ). 
     According to another embodiment, a sealing limb ( 15 D) of the adapter collar ( 15 ), which is parallel to the protuberance is provided. 
     According to yet another embodiment, a reception groove ( 15 E), which is formed from a limb ( 15 B), which is parallel to the protuberance, and a sealing limb ( 15 D), which is parallel to the protuberance, of the adapter collar ( 15 ), for the protuberance ( 13 ) of the filter holder ( 12 ). 
     According to a further embodiment, at least one bead-like protrusion ( 16 C) of the sealing arrangement ( 16 ) and a corresponding recess on the adapter collar ( 15 ) is/are provided. 
     According to yet a further embodiment, provided is a corresponding grooving and ribbing ( 18 A;  18 B) between limbs of the sealing arrangement and of the adapter collar that are parallel to the plate. 
     Yet even further, any of the these embodiments can be combined with other embodiments forming yet even further embodiments. 
     Further, while considerable emphasis has been placed on the preferred embodiments of the invention illustrated and described herein, it will be appreciated that other embodiments, and equivalences thereof, can be made and that many changes can be made in the preferred embodiments without departing from the principles of the invention. Furthermore, the embodiments described above can be combined to form yet other embodiments of the invention of this application. Accordingly, it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the invention and not as a limitation.