Abstract:
The invention relates to a gas filter insert ( 1 ), particularly an air filter insert for a fresh air system of an internal combustion engine, having a filter body ( 2 ) which extends in its longitudinal direction ( 4 ) in a U-shape around an inner chamber ( 5 ), and having a connector ( 3 ) which communicates with the inner chamber ( 5 ) and is arranged on the filter body on the open end-face side ( 7 ) thereof. In order to simplify the construction of the filter insert ( 1 ), the filter body ( 2 ) is sealed transversally to its longitudinal direction ( 4 ), with an end plate ( 9 ) on at least one end side ( 8 ).

Description:
CROSS-REFERENCES TO RELATED APPLICATION 
     This application is a National Stage application which claims the benefit of International Application No. PCT/EP2008/055684 filed May 23, 2007, which claims priority based on German Application No. 10 2007 024 287.7, filed May 8, 2008, both of which are hereby incorporated by reference in their entirety. 
     The present invention relates to a gas filter insert, in particular an air filter insert for a fresh air system of an internal combustion engine, having the features of the preamble of claim  1 . The invention furthermore relates to a gas filter equipped with such a filter insert. 
     TECHNICAL FIELD 
     Document DE 103 28 002 A1 discloses a gas filter insert having a filter member and a connection. The filter member extends in its longitudinal direction in a “U”-shaped manner around an interior chamber. The connection communicates with the interior chamber and is arranged on the filter member on its open front face. 
     BACKGROUND 
     In known gas filter inserts, the filter member is sealed on its end sides transversely to its longitudinal direction in such a manner that the folded sheet material forming the filter member is configured in the region of these end sides to be correspondingly airtight, for example the end edges can be welded. In the known gas filter inserts, a sealing is provided on the end sides of the filter member on an edge that is adjacent the interior chamber, said sealing acting together with a housing, in the assembled state, in order to separate in the housing a crude chamber from a pure chamber. 
     The present invention addresses the problem of providing an improved or at least a different embodiment of a gas filter insert of the previously mentioned type, said improvement or different embodiment being characterised by a simplified and thus more economical configuration. 
     This problem is solved according to the invention by the subject matter of the independent claims. Advantageous embodiments are the subject matter of the dependent claims. 
     SUMMARY 
     The invention is based on the general concept of realising the sealing of the filter member transversely to a longitudinal direction at least on one end side by means of an end plate. By means of such an end plate, the respective filter material forming the filter member can be sealed in its entirety on the end side concerned, by means of which a comparably expensively manufactured sealing of the filter material, even just in the region of the respective end side, can be dispensed with. For example, all end edges of the filter material can be sealed on the respective end side with the respective end plate. The sealing of the filter member on the respective end side can be realised by means of the used end plate, in that, for example, the filter member is encased in plastic in the end plate on the end side concerned or is adhered to the end plate by means of using a suitable adhesive material or is welded to the end plate. By using the at least one end plate, the stability of the filter insert can moreover be improved, which can resultantly introduce in particular an increased operational reliability with regard to the sealing in the assembled state. 
     It is preferred that the filter member is sealed on both end side respectively with such an end plate. 
     According to a particularly advantageous embodiment, the respective end plate can be configured as closed, particularly in such a manner that it seals the interior chamber of the respective end side of the filter member at least in the assembled state. With this manner of construction, an additional sealing attached to the filter member or to the respective end plate can be dispensed with. In particular, the separation of a pure chamber from a crude chamber occurs in such a manner substantially exclusively by means of the filter insert, without necessitating the co-operation with the housing of the associated gas filter in the assembled state. This increases the operational reliability of the gas filter even with relatively large production tolerances. 
     Additional important features and advantages of the invention can be found in the dependent claims, in the drawings, and in the pertinent description of the figures with reference to the drawings. 
     It is understood that the features described above and those to be described in what follows can be used not only in the particular cited combination; but also in other combinations or independently without departing from the scope of the present invention. 
     Preferred embodiments of the invention are shown in the drawings and are described in more detail in the following description, the same reference numerals referring to components which are the same or functionally the same or similar. 
    
    
     
       BREIF DESSCRIPTION OF THE DRAWING 
       It is schematically shown in 
         FIG. 1  a very simplified longitudinal cross-section of a gas filter insert corresponding to the line of intersection I in  FIG. 2 , 
         FIG. 2  a section view of the gas filter insert corresponding to the line of intersection II in  FIG. 1 , 
         FIG. 3  a view of the gas filter insert corresponding to a viewing direction III in the  FIGS. 1 and 2 , 
         FIGS. 4-6  an enlarged detail view of an end plate of the gas filter insert in a different embodiments and/or in different section of the end plate, 
       FIGS.  7 + 8  section view as in  FIG. 2 , however only in the region of a connection, in different embodiments, 
         FIG. 9  a longitudinal cross-section as in  FIG. 1  of a gas filter. 
     
    
    
     DETAILED DESCRIPTION 
     Corresponding to the  FIGS. 1 to 9 , a gas filter insert  1  comprises a filter member  2  and a connection  3 . The filter member  2  extends in a longitudinal direction  4  indicated by a dot and dash line in  FIG. 1  in a substantially “U”-shape around an interior chamber  5 . The filter member  2  preferably consists of a suitable filter material  6  that in particular can be folded or pleated in a zigzag manner. The filter member  2  has an open front face  7  because of its “U” shape. 
     The connection  3  communicates with the interior chamber  5  and is arranged on the open front face  7  of the filter member  2 . 
     The filter member  2  has an end side  8  transverse to its longitudinal direction  4 . The filter member  2  is sealed with an end plate  9  on at least one of these end sides  8 . In the embodiment shown here, the filter member  2  is respectively sealed on both end sides  8  with such an end plate  9 . In theory, however, an embodiment is also conceivable in which the filter member  2  is sealed only in the region of one of its end sides  8  with such an end plate  9 . 
     The sealing of the respective end sides  8  of the filter member  2  by means of the respective end plates  9  can preferably be realized in that the filter member  2  along with its end side  8  is encased in plastic in the respective end plate  9 . Alternatively, it is likewise possible to weld or adhere the filter member  2  to the respective end side  8  with the respective end plate  9 . 
     In the preferred embodiment shown here, the respective end plate  9  is configured as closed. It is thereby achieved that the interior chamber  5  on the respective end side  8  of the filter member  2  is closed, thereby making it possible to dispense with additional sealing measures. In order to make reaching or removal from the interior chamber  5  possible, the respective gas must penetrate the filter member  2  with a closed end plate  9 . It is not excluded that the respectively closed end plate  9  corresponding to figure can contain at least one opening  10 . However, in the assembled state of the gas filter insert  1 , said opening is closed in a sealed manner by means of a fastening element  11 . The fastening element  11  is here formed by a screw that is supported on the end plate  9  by a sealing disc  12 , which thereby closes the opening  10  in a sealed fashion. 
     Additionally or alternatively, the respectively closed end plates  9  according to  FIG. 5  can have at least one hollow foot  13 . This hollow foot  13  protrudes into the interior chamber  5  and is open in the region of the respective end side  8  of the filter member  2 . The corresponding open side is characterised with reference numeral “ 14 ” in  FIG. 5 . The foot  13  can, for example, be used to support the one end plate  9  on a housing or on the other end plate  9 , either directly or, as is indicated in  FIG. 5 , or by means of a corresponding foot  13  of the other end plate  9 . The foot  13  likewise can be used to fasten the gas filter insert  1  in the assembled state through an opening  10  by means of a corresponding fastening element  11 . The stability of the gas filter insert  1  can be considerably improved by means of the supported foot  13 . 
     Although the respective end plate  9  cannot be entirely closed in the unassembled state by means of such an opening  10  or by means of such a foot  13  that likewise can contain such an opening  10 , it can sufficiently seal in a gas-tight manner the interior chamber  5  in the assembled state since the respective opening  10  in the assembled state is closed in a sealed manner by, for example, a corresponding fastening element  11 . 
     The stability of the respective end plate  9  can also be increased by the formation of ribs  15 , as in  FIG. 6 . These can preferably be configured in a recess  16 , which is set back, of the respective end plate  9  in the direction of the interior chamber  5  and be substantially flush with the remaining exterior side of the end plate  9 . 
     At least corresponding to the  FIGS. 1 to 3 , the connection  3  in this preferred embodiment is configured on a front plate  17 . This front plate  17  is then arranged on the open front face  7  of the filter member  2 . The front plate  17  can be attached to the filter member  2  of the respective end plate  9 . The front plate  17  is connected on the front ends of the “U” bracket of the filter member  2  therewith or by means of the filter material of the filter member  2 . For example, the front plate  17  can be adhered to the filter member  2  and the end plates  9  on the front face. It is also likewise possible in principle to weld or to connect by means of encasing in plastic the front plate  17  to the respective end plate  9  and/or to the filter member  2 . 
     It is preferred to manufacture integrally the connection  3  with the associated front plate  17  out of one piece as an injection-moulded part, for example. 
     The front plate  17  can be clipped with the respective end plate  9 , corresponding to the embodiment shown in  FIGS. 1 to 3 . Correspondingly, the clips configured on the end plate  9  are characterised with reference numeral “ 18 ”. 
     Notable here is a special embodiment in which the front plate  17  is not only clipped to the respective end plate  9  but is also adhered to the respective end plate  9  as well as to the filter member  2 . This embodiment is characterised by its simplicity to manufacture. During the hardening process of the adhesive material, the clipping of an adequate position fixation and the pressing of the front plate  17  on the respective end plate  9  as well as on the filter member  2 . Subsequent to the hardening of the adhesive, the clipping is no longer necessary in and of itself. 
       FIG. 7  shows an embodiment in which the connection  3  or the optionally present front plate  17  is foamed onto the filter member  2  and onto the respective front face of the end plate  9 . A corresponding foam is characterised in  FIG. 7  with reference numeral “ 19 ”. A foam  19  correspondingly suited therefor can have, for example, closed pores and can consist of polyurethane, for example. 
       FIG. 8  shows an embodiment in which the front plate  17  and at least one of the end plates  9  are manufactured from one integral piece. For example, the respective end plates  9  and the front plate  17  can be injection moulded in one injection mould as a common component. The front plate  17  and the respective end plate  9  can be connected one to the other, in particular by means of an integral hinge  20 . In this manner, the injection-moulding process or the tools necessary therefor can be simplified. The one-component configuration can offer advantages with regard to assembly. 
     The connection  3  is configured here in such a manner that it can hold a radial sealing  21 , in particular an “O”-ring seal. Corresponding hooks  22  are configured for this purpose, said hooks being arranged distributed in the circumferential direction and that radially engage in segments the respective radial sealing  21  in order to position it in its position. 
     Corresponding to  FIG. 9 , a gas filter  23  comprises a housing  24  and a gas filter insert  1  of the previously-described type. The housing  24  has an inlet  25  on the crude side and an outlet  26  on the pure side. The gas filter insert  1  is inserted into the housing  24  in the assembled state and thereby separates a crude chamber from a pure chamber. In the example shown, the connection  3  of the gas filter insert  1  is connected to the outlet  26 . Accordingly, an interior chamber  27  of the housing  24  forms the crude chamber, while the interior chamber  5  of the filter insert  1  forms the pure chamber. It is evident that in theory, a direction of flow in the reverse direction can also be present. 
     The gas filter  23  or the gas filter insert  1  are preferably configured as an air filter or an air filter insert and can be used, for example, in a fresh air system of an internal combustion engine, which can be arranged in a motor vehicle, in particular.