Abstract:
An assembly for an air conditioning system may include an air filter for filtering drawn-in fresh air. The air filter may be arranged in a fresh air path and may separate a raw side from a clean side of the fresh air path. A water path for discharging water separated from the fresh air may be disposed at the raw side of the air filter. The water path may include a water filter for filtering the separated water. The water filter may separate a raw side from a clean side of the water path.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority to German Patent Application No. 10 2014 202 368.8, filed Feb. 10, 2014, the contents of which are hereby incorporated by reference in their entirety. 
       TECHNICAL FIELD 
       [0002]    The present invention relates to an assembly for an air conditioning system for air conditioning an interior of a vehicle. The present invention further relates to an air conditioning system equipped with such an assembly. The present invention relates furthermore to an air filter for such an assembly or respectively for such an air conditioning system. 
       BACKGROUND 
       [0003]    Usually, an air conditioning system comprises a fresh air inlet for drawing in fresh air from an environment of the vehicle. In addition, an air conditioning system is usually equipped with an air filter for filtering drawn-in fresh air, which is arranged in a fresh air path and separates therein a raw side from a clean side. On the raw side of the air filter, a deposition of water can occur, which may be contained in the fresh air, e.g. rain water or condensate. A water path conveys the separated water away. In addition, a water box can be optionally provided for collecting and conveying away water separated from the fresh air which, with respect to a fresh air flow occurring in the operation of the air conditioning system, is arranged upstream of the air filter, i.e. in the raw side of the fresh air path. 
         [0004]    Such a water box forms a type of drainage, by means of which water which is carried in the fresh air can be discharged. The arrangement of such a drainage upstream of the air filter leads to a reduced stress of the air filter by water, which improves the service life of the air filter. 
         [0005]    In addition, in such an air conditioning system it can be expedient to discharge the water, which is separated by means of such a drainage arrangement, together with condensation water which may occur within the air conditioning system. In an air conditioning system, condensation water can occur especially when a cooling device is arranged within the fresh air path, by means of which the drawn-in fresh air is cooled. Frequently here, the dew point of water is fallen below, whereby entrained water condenses and accumulates as liquid condensate. Such a cooling below the dew point of water is frequently desired within the air conditioning system, in order to bring about, alongside an efficient cooling of the fresh air, a drying of the fresh air at the same time. 
         [0006]    A problem in the feeding of the drainage water to the condensate is the fact that the drainage water occurs on the raw side, whereas the condensate occurs on the clean side, so that impurities which are entrained in the drainage water can also contaminate a path serving for the discharging of the drainage water and of the condensation water. Furthermore, a drainage path leading the drainage water from the raw side to the clean side forms a bypass for bypassing the air filter, if no or only a little drainage water occurs, so that unpurified fresh air arrives at the clean side of the fresh air path via the drainage path. Hereby, the efficiency of the air filtration is reduced. 
       SUMMARY 
       [0007]    The present invention is concerned with the problem of indicating for an air conditioning system of the type named in the introduction a way for an improved embodiment, which is distinguished in particular by an improved cleaning effect for drawn-in fresh air. 
         [0008]    This problem is solved according to the invention by the subject matter of the independent claim. Advantageous embodiments are the subject matter of the dependent claims. 
         [0009]    The invention is based on the general idea of providing an assembly for the air conditioning system, in which a water filter is to be arranged in the water path, which separates a raw side from a clean side in the water path. The water filter serves here for filtering the separated water. Through the water filter on the one hand impurities which are situated in the separated water are filtered out, so that only purified drainage water arrives at the clean side of the water path. The risk of a contamination of the water path is thereby reduced. This also applies to the case in which the drainage water is fed on the clean side of the water path and condensation water on the clean side of the fresh air path, so that also a condensation water path or respectively a shared discharge path is protected from impurities. On the other hand, the water filter forms a flow resistance for fresh air, whereby the risk of a bypass flow which bypasses the air filter is reduced. Even if a bypass flow bypassing the air filter were to occur along the water path, for example, in the case of a lack of drainage water, the bypass flow must flow through the water filter, whereby also the bypass stream is subjected to a filtration which filters out impurities from the bypass stream. The assembly which is presented here contains here a section of the fresh air path in which the air filter is arranged, if applicable with corresponding air filter holding means for fixing the air filter within the assembly. Furthermore, the assembly which is presented here contains at least one section of the water path in which the water filter is arranged, if applicable with corresponding water filter holding means for fixing the water filter within the assembly. 
         [0010]    Advantageously, the assembly provided for the air conditioning system can have in the water path a water box for collecting and discharging the separated water. The water box is advantageously arranged here at or in the raw side of the fresh air path. In the water box, therefore, the accumulating water can be collected particularly simply and discharged via the remaining water path. 
         [0011]    A further development is now particularly advantageous, in which the water filter is arranged in the water box. A comparatively large amount of installation space is available in the water box for accommodating the water filter, so that a relatively large purification capacity is able to be realized, without the risk arising of a blockage of the water path. 
         [0012]    According to an advantageous embodiment, the water box can be arranged at a lower end of the air filter and can have an upwardly open water inlet opening. The terms “down” and “up” refer here to a normal installation situation of the air conditioning system in a vehicle, the wheels of which are placed normally on a roadway. “Upward” is therefore facing away from the roadway, whereas “downward” is facing the roadway. The upwardly open water box at the lower end of the air filter leads to water, which is entrained in the raw-side fresh air stream, entering due to gravity downward into the water box. Furthermore, a compact structural form is thereby achieved, because the water box is situated directly at the air filter. In particular, it is conceivable to configure the air filter so that it is indeed permeable for fresh air, but not for entrained water, so that the air filter has a water-separating effect. The water which is separated at the air filter flows off, due to gravity, downward at the air filter in the direction of the water box. It is likewise conceivable to provide a drainage arrangement immediately upstream of the air filter, which separates water entrained in the fresh air stream and feeds it directly to the water box. For example, a drainage structure is conceivable, which is opaque in the main flow direction of the drawn-in fresh air, so that multiple flow deflections are necessary, in order to flow through the drainage structure. The light fresh air can follow these flow deflections readily and without a major drop in pressure, whereas the entrained heavier impurities, in particular water drops, cannot follow these deflections owing the centrifugal forces and instead strike onto impact walls, which in particular form channels and can lead to the water box. 
         [0013]    According to an expedient further development, the air filter can have a filter body of a filter material and at least one end plate arranged laterally on the filter body. Hereby, the production of the air filter is simplified. The water box can now be formed integrally on such an end plate of the air filter. Accordingly, in this embodiment, the water box forms an integral component of the air filter. The integral construction type leads to an advantage with regard to assembly. Furthermore, an additional seal between the water box and the air filter can be dispensed with, because the water box can be readily integrated so that the necessary seal exists between water box and filter body. 
         [0014]    According to another embodiment, the water filter can have a filling of a filter material, wherein the filling is either filled directly into the water box or into a bag which is inserted into the water box. The bag itself consists of a material which is permeable for water and for the usual impurities, in particular a woven fabric. Such a filling has a particularly high dirt retention capacity, wherein at the same time it only produces a comparatively small drop in pressure. Alternatively, the water filter can also have a shaped non-woven material or a filter foam as filter material, wherein the non-woven material or respectively the foam is inserted into the water box. 
         [0015]    According to another embodiment, the water filter can have a cover of non-woven material, which covers a water inlet opening of the water box. Hereby, on the one hand it is brought about that any fluid, i.e. in particular separated water and fresh air, is filtered before it arrives into the water box. On the other hand, the cover of non-woven material brings about a closure of the water inlet opening, which holds back a filling which is filled, if applicable, into the water box. 
         [0016]    According to another embodiment, the water box can be elongated and can have a water outlet opening at one longitudinal end, through which filtered water can exit. It has been found that by means of such a lateral or face-side water outlet opening a particularly compact type of construction is able to be realized. 
         [0017]    According to a further development, the water box can have a base which has a slope in the direction of the water outlet opening. Through the slope, a sump formation in the water box can be avoided. Bacteria and other microorganisms could proliferate in a sump through standing water, which is basically undesirable. 
         [0018]    According to another embodiment, the air filter and the water filter can be arranged so that a filter material of the air filter and a filter material of the water filter do not touch each other. By avoiding a direct contact of the filter materials of air filter and water filter, capillary effects can also be avoided, which could cause the filter material of the air filter to become soaked with water from the water filter. 
         [0019]    In another embodiment, the assembly formed from the air filter and the water filter can form an installation unit which can be arranged exchangeably on a housing of the air conditioning system. Hereby, a particularly simple installation or respectively maintenance is produced, including exchange of the entire assembly or respectively installation unit, for the air conditioning system, because the said components are already in a predetermined relative position to one another within the installation unit. Furthermore, the sealing of the individual components with respect to one another is simplified. Moreover, the case of maintenance is simplified in which the air filter and the water filter are exchanged. In so far as such an installation unit is present, the complete installation unit can be exchanged particularly simply. Preferably, the installation unit also comprises the water box. 
         [0020]    According to another embodiment, the filter material of the air filter can have an adsorption means, for example in order to filter out odorants from the air stream. In another advantageous embodiment, the filter material of the water filter can have an adsorption means, for example in order to filter out odorants from the separated water. It is noteworthy here that the odour-absorbing water filter also acts in an odour-adsorbing manner for the air flow, because the odorants, due to their molecular movements, can also strike onto the water filter and can be absorbed there by the adsorption means. Activated carbon and suchlike come into consideration as adsorption means both for the air filter and also for the water filter. 
         [0021]    In an alternative embodiment, the water filter can also be arranged in the water path downstream of the water box, in so far as sufficient installation space is available there. In particular, the water filter can then also be arranged in a feed line which leads away from the water box and feeds the separated, purified water to a condensate discharge, which discharges condensate of a condenser or air cooler which is present if applicable. 
         [0022]    An air conditioning system according to the invention is equipped with at least one assembly of the type described above. Here, the air conditioning system provides a fresh air duct into which the assembly is incorporated and in particular can be installed as an assembly unit. In the fresh air duct, the fresh air path is directed to the assembly and conveyed away therefrom. 
         [0023]    In an advantageous embodiment of the air conditioning system, an air cooler can be arranged in the air path downstream of the air filter, by means of which air cooler the drawn-in fresh air can be cooled. This air cooler can have a condensate discharge, by means of which condensate occurring during the cooling of the fresh air can be discharged. A further embodiment of the air conditioning system is now particularly expedient, in which the clean side of the water path is connected fluidically to the condensate discharge. Consequently, in addition to the condensate, drainage water can also be discharged via the condensate discharge. Through the water filter in the water path, a contamination of the condensate discharge is thereby avoided. 
         [0024]    An air filter according to the invention is distinguished by a filter body of a filter material, which has laterally at least one end plate, wherein on such an end plate a water box is integrally formed for collecting and discharging water separated from the fresh air. Through this type of construction, the air filter forms an assembly or unit having a high functional density, which simplifies the installation of the air conditioning system or respectively the maintenance. 
         [0025]    Further important features and advantages of the invention will emerge from the subclaims, from the drawings and from the associated figure description with the aid of the drawings. 
         [0026]    It shall be understood that the features mentioned above and to be further explained below are able to be used not only in the respectively indicated combination, but also in other combinations or in isolation, without departing from the scope of the present invention. 
         [0027]    Preferred example embodiments of the invention are illustrated in the drawings and are explained in further detail in the following description, wherein the same reference numbers refer to identical or similar or functionally identical components. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0028]    There are shown, respectively diagrammatically, 
           [0029]      FIG. 1  a greatly simplified longitudinal section of an air conditioning system in the region of an air filter, 
           [0030]      FIG. 2  a top view of the air conditioning system in the region of the air filter according to a viewing direction II in  FIG. 1 . 
       
    
    
     DETAILED DESCRIPTION 
       [0031]    According to  FIGS. 1 and 2 , an air conditioning system  1 , by means of which an interior of a vehicle, not shown here, can be air-conditioned, comprises a fresh air path  2 , indicated by arrows, which connects a fresh air inlet  3  on the inlet side with at least one fresh air outlet, not shown here, which opens into said vehicle interior. The fresh air inlet  3  is open to an environment  4  of the vehicle, so that the fresh air can be drawn in from the environment  4  and conveyed along the fresh air path  2 . The fresh air path  2  can be delimited laterally here in a conventional manner by walls  5 , which form for example a fresh air duct  6 . The air conditioning system  1  comprises an air filter  7 , through which the fresh air path  2  is directed. The air filter  7  is arranged here in the fresh air path  2  so that it separates a raw side  8  from a clean side  9  in the fresh air path  2 . With respect to a fresh air flow, following the fresh air path  2 , which occurs in operation of the air conditioning system  1 , the raw side  8  is situated upstream of the air filter  9 , whereas the clean side  9  is then arranged downstream of the air filter  7 . 
         [0032]    The air conditioning system  1  is equipped in addition with a drainage arrangement  10 , by means of which water entrained in the drawn-in fresh air can be separated. The drainage arrangement  10  comprises here a water box  11  for collecting and discharging water which is separated from the fresh air. The water box  11  is arranged here on the raw side  8  of the fresh air path  2 , i.e. upstream of the air filter  7  with respect to the fresh air flow. In the preferred embodiment which is shown here, a water filter  12  is arranged in the water box  11 , by means of which the separated water can be filtered. The water filter  12  is arranged here in a water path  13 , which is indicated by arrows in  FIGS. 1 and 2 . Here, in the water path  13 , the water filter  12  separates a raw side  14  from a clean side  15  of the water path  13 . 
         [0033]    Irrespective of whether the water filter  12  is arranged in the water box  11 , and irrespective of whether a water box  11  is provided at all, the air filter  7  and the water filter  12  form components of an assembly  37  within the air conditioning system  1 . This assembly  37  therefore comprises a section of the fresh air path  2 , in which the air filter  7  is arranged, and at least one section of the water path  13 , in which the water filter  12  is arranged. Preferably, however, the water box  11  also belongs to the assembly  37 , especially when the water filter  12  is arranged in the water box  11 . 
         [0034]    According to the embodiment which is shown here, the water box  11  is arranged at a lower end  16  of the air filter  7 . In addition, the water box  11  has an upwardly open water inlet opening  17 , which is covered in  FIG. 1  by a cover of non-woven material  18 . In the example, provision is further made that the water box  11  and the air filter  7  form a cohesive installation unit  19 , which can be incorporated as a whole into the fresh air system  1  or respectively can be exchanged for maintenance purposes. The fresh air duct  6  forms here a component of a housing  36  of the air conditioning system  1 , in which the air filter  7  and the water filter  12  or respectively the entire assembly  37  or respectively the installation unit  19  is exchangeably incorporated. The assembly  37 , configured as installation unit  19 , can then be offered as an initial equipment part or as a service part and installed in the air conditioning system  1 . 
         [0035]    The assembly  37 , configured as installation unit  19 , can expediently have a support structure  38 , which can optionally have air filter holding means, not shown here or respectively not necessary, for fixing the air filter  7  on the support structure  38  and/or water filter holding means, not shown here or respectively not necessary, for fixing the water filter  12  on the support structure  38 . In the example, the water box  11  is formed integrally on the support structure  38 . Likewise, the support structure  38  has fastening means  39  here for fixing the installation unit  19  on a housing  36  of the air-conditioning system  1 . Counter-fastening means  40 , complementary to the fastening means  39 , are formed on the housing  36 , which counter-fastening means are suitable in particular for realizing a quick fastening. In the example, the fastening means  39  and the counter-fastening means  40  form a groove-and-tongue connection  41 , which is distinguished by sufficient tightness, high mechanical strength and being able to be realized in a simple manner. As illustrated, the air filter  7  can be mounted on the support structure  38 . 
         [0036]    The air filter  7  can have, for example, a filter body  20  which consists of filter material and is flowed through by the fresh air flow in the operation of the air conditioning system  1 . The filter body  20  can be enclosed here laterally by end plates  21 . These can be produced for example from a plastic. According to  FIG. 1 , the water box  11  or respectively the previously mentioned support structure  38  can be formed integrally with a (lower) end plate  21  provided at the lower end  16 . The water box  11  is thereby formed in one material with this lower end plate  21 . In so far as more than one end plate  21  is provided, two or more end plates can be produced in one material, i.e. from one piece. In so far as four end plates  21  are provided, these can form a completely circumferential frame, laterally enclosing the filter body  20 . In  FIG. 1  in addition a reinforcing rib  22  is indicated, which increases the rigidity of the connection between water box  11  and lower end plate  21 . In so far as the installation unit  19  is present, the water box  11 , the end plates  21 , the said frame and the reinforcing ribs  22  which are present if applicable, are respectively a component of the installation group  37  and in particular formed on the support structure  38 , preferably by an integral forming in one material. 
         [0037]    Expediently, the water filter  12  can be formed by a filling  23  of a filter material, wherein the filling  23  can be filled directly into the water box  11 . However, an embodiment is preferred in which the filling  23  itself is filled into a bag, not illustrated here, of a material which is permeable for the water, which bag is inserted into the water box  11 . Hereby, it can be prevented in particular that the filling  23  is flushed out from a water outlet opening  24  of the water box  11 . It is likewise conceivable to arrange specifically only at the water outlet opening  24  a retention element  25  which is permeable for water but is impermeable for the filter material, which retention element is indicated in  FIG. 2  and can be formed for example by a woven fabric or a non-woven material. 
         [0038]    As can be seen from  FIGS. 1 and 2 , the water box  11  is equipped with an elongated geometry, so that a box longitudinal direction  26  runs transversely to a duct longitudinal direction  27  and substantially horizontally. In addition, a box length measured parallel to the box longitudinal direction  26  is greater than a box width measured parallel to the duct longitudinal direction  27  and a box height measured vertically. The water outlet opening  24  is arranged here at a face-side longitudinal end  28  of the water box  11 . The filtered drainage water exits through the water outlet opening  24 . According to  FIG. 1 , the water box  11  has on its underside a base  29 . The base  29  has a slope, not noticeable here, in the direction of the water outlet opening  24 , so that the base  29  drops towards the water outlet opening  24 . In other words, the previously mentioned box height decreases with an increasing distance from the water outlet opening  24 . The base  29  is also inclined here with respect to a horizontal plane, so that gravity drives the water along the base  29  in the direction of the water outlet opening  24 . 
         [0039]    Expediently, the air filter  7  and the water filter  12  are arranged within the previously mentioned installation unit  19  so that the filter material, of which the filter body  20  consists, and the filter material of the water filter  12 , which can be formed for example by the previously mentioned filling  23 , to not touch each other. The filter material of the air filter  7  can have here an adsorption means. Additionally or alternatively, the filter material of the water filter  12  can have an adsorption means. An activated carbon granulate comes into consideration here, for example, as adsorption means. In the case of the water filter  12 , such an activated carbon granulate can be mixed into the remaining filling  23  of the filter material. Likewise, it is basically possible to form the said filling  23  exclusively from such adsorption means. 
         [0040]    According to  FIG. 1 , the air conditioning system  1  can have an air cooler  30  in the fresh air path  2  downstream of the air filter  7 , by means of which the drawn-in fresh air can be cooled. For this, the air cooler  30  can be connected for example to a suitable cooling circuit  31 . The air cooler  30  is equipped with a condensate discharge  32 , by means of which condensate, if applicable occurring in the air cooler  30 , can be discharged from the air cooler  30  and out from the fresh air duct  6 . Expediently, the clean side  15  of the water path  13  is now connected fluidically to this condensate discharge  32 . A corresponding connection site is designated by  33  in  FIG. 1 . As the drainage water is purified by means of the water filter  12 , the condensate discharge  32  can be used particularly favourably for the discharging of the drainage water, without the risk of a contamination of the condensate discharge  32  being increased here. 
         [0041]    According to an advantageous embodiment, the drainage arrangement  10  can have a drainage structure  34  arranged in the fresh air duct  6 , which drainage structure must be flowed through by the fresh air flow, wherein the water, entrained in liquid form, can be separated. This is achieved expediently by means of inertial separation. Such an inertial separation can be achieved for example in that the fresh air flow is deflected several times within the drainage structure  34 , such that the fresh air can readily follow the deflections, whilst entrained particles, in particular water droplets, cannot follow these flow deflections owing to their great mass, but rather strike onto impact surfaces of the drainage structure  34  which are provided specifically for this. The impact surfaces can be formed by pipes which are open on one side, which then discharge the drainage water accumulating therein to the water box  11 . In the example of  FIG. 1  such a drainage structure  34  is arranged at an inlet side  35  of the filter body  20  which is flowed against by the fresh air flow during operation. In particular, the drainage structure  34  can be integrated into the air filter  7  or respectively into the previously mentioned installation unit  19 .