Abstract:
A fresh air supply device for an internal combustion engine may include a filter element arranged in a filter compartment. A charge-air cooler may be arranged in a cooler compartment. A one-piece housing may integrally include the filter compartment and the cooler compartment. The charge-air cooler may have a coolant inlet, a coolant outlet and an internal coolant path which connects the coolant inlet to the coolant outlet. The internal coolant path may be coupled in a heat-transferring manner to a charge-air path extending inside the housing and through the cooler compartment.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority to German Patent Application No. 10 2012 213 164.7, filed Jul. 26, 2012, and International Patent Application No. PCT/EP2013/065425, filed Jul. 22, 2013, both of which are hereby incorporated by reference in their entirety. 
     
    
     TECHNICAL FIELD 
       [0002]    The present invention relates to a fresh air supply device for an internal combustion engine, in particular of a motor vehicle, having the features of the introductory clause of claim  1 . 
       BACKGROUND 
       [0003]    A fresh air supply device which supplies a supercharged internal combustion engine with fresh air usually comprises a filter element, which is arranged in a filter compartment, and a charge-air cooler, which is arranged in a cooler compartment. For charging the fresh air, the internal combustion engine comprises, for example, a compressor or an exhaust gas turbocharger, which has a supercharger coupled with a fresh air system of the internal combustion engine and a turbine in drive-connection with the supercharger, which turbine is integrated into an exhaust gas system of the internal combustion engine. 
         [0004]    From DE 196 04 738 A1 a fresh air supply device is known, which contains in a shared housing the filter compartment for receiving the filter element and the cooler compartment for receiving the charge-air cooler. Here, the housing is constructed so that an air stream supplied to the housing is divided in the housing into two partial streams. The one partial stream flows through the filter element, whilst the other partial stream flows through the charge-air cooler for cooling the charge air. For this, the one partial stream, after it has flowed through the filter element, is directed out from the housing and is supplied to a supercharger of an exhaust gas turbocharger. From the supercharger, the supercharged fresh air, i.e. the charge air, arrives back into the housing and flows through the charge-air cooler, from which then the cooled charge air is directed on to combustion chambers of the internal combustion engine. The efficiency of such a fresh air supply device is comparatively low with regard to the cooling capacity which is able to be achieved, if a compact type of construction is aimed for. 
         [0005]    From DE 27 38 293 A1 a further fresh air supply device for a supercharged internal combustion engine is known, in which in a shared housing the filter element and, downstream therefrom, the charge-air cooler are arranged in a shared interior of the housing. The air purification in this fresh air supply device therefore takes place after the supercharging. 
       SUMMARY 
       [0006]    The present invention deals with the problem of indicating for such a fresh air supply device an improved embodiment which is distinguished in particular by being able to be produced economically. Furthermore, a compact structural form and a high efficiency are to be realized. 
         [0007]    This problem is solved in the present invention in particular by the subject of the independent claim. Advantageous embodiments are the subject of the dependent claims. 
         [0008]    The present invention is based on the general idea, for accommodating the charge-air cooler and the filter element, of providing a one-piece housing which has the filter compartment and the cooler compartment integrally. In other words, the filter compartment and the cooler compartment are formed integrally as separate compartments at the same housing. Through such a one-piece housing, a particularly simple structure and a capability for the fresh air supply device to be manufactured particularly economically are the result. 
         [0009]    Furthermore, the invention proposes equipping the charge-air cooler with a coolant inlet, with a coolant outlet and with an internal coolant path connecting the coolant inlet with the coolant outlet, which coolant path is coupled in a heat-transferring manner with a charge-air path running in the housing and directed through the cooler compartment. Through the integrated or respectively internal coolant path, the charge-air cooler can be operated in particular with a liquid coolant, whereby a particularly intensive charge-air cooling is able to be realized with a small installation space. Such a charge-air cooler of compact construction can be accommodated in a particularly simple manner in the proposed shared, one-piece housing, which considerably simplifies the manufacture of the housing as a one-piece component. 
         [0010]    According to a preferred embodiment, the charge-air cooler can be constructed as a component which is able to be inserted, in particular able to be pushed into the cooler compartment. This permits a simple installation of the charge-air cooler in the housing; for maintenance or repair purposes, the charge-air cooler can be removed accordingly simply again from the housing of the fresh air supply device. 
         [0011]    According to an advantageous further development, the charge-air cooler can have a cover body which has the coolant inlet and the coolant outlet and which closes a cooler compartment opening provided on the housing, through which the charge-air cooler is inserted into the cooler compartment. Hereby, a component of the charge-air cooler, namely the cover body, is given a multiple functionality. On the one hand, it forms a structural component of the charge-air cooler, which has a certain carrying function. On the other hand, the cover body forms a cover or closure for the cooler compartment opening of the housing. At the same time, the connecting of the charge-air cooler to a cooling circuit is thereby considerably simplified, because the coolant inlet and the coolant outlet are formed on this cover body, so that no separate aperture through a housing wall has to be provided and sealed. 
         [0012]    According to an advantageous embodiment, the housing has a fresh air inlet for unfiltered and non-compressed fresh air, through which air can enter into the housing from the environment. Furthermore, the housing is expediently equipped with a charge-air outlet, through which filtered, supercharged and cooled charge air can emerge from the housing can be supplied to combustion chambers of the internal combustion engine. 
         [0013]    According to another advantageous embodiment, a throttle device can be provided, the throttle member of which is arranged in a throttle compartment, which is formed integrally in or respectively on the housing. Hereby, the functional density of the housing is increased, which reduces the production costs. 
         [0014]    According to an advantageous further development, the throttle device can be a unit which is able to be preassembled, which is added on to the housing so that the throttle member is inserted into the throttle compartment. This type of construction simplifies the assembly of the fresh air supply device, because only the preassembled throttle device has to be inserted or respectively added. 
         [0015]    According to another further development, the throttle device can have a closure section, which closes a throttle compartment opening provided on the housing, through which the throttle member is inserted into the throttle compartment. Therefore, the functional density of the throttle device is increased. At the same time, the assembly of the fresh air supply device is simplified, because through the adding on of the throttle device, at the same time the throttle compartment opening, which is present for the introduction of the throttle member, can be closed. 
         [0016]    An embodiment is particularly advantageous here in which the closure section of the throttle device can be connected by a clip connection with the housing. Hereby, additional separate fastening elements are dispensed with. 
         [0017]    In another advantageous embodiment, an air mass sensor can be provided, the sensor system of which is arranged in a sensor compartment, which is formed integrally in or respectively on the housing. Through this measure, the functional density of the housing is increased, which reduces the manufacturing costs as a whole. The sensor compartment opens expediently into a clean side of the filter compartment: is therefore arranged downstream of the filter element in the fresh air path. 
         [0018]    According to an advantageous further development, the air mass sensor can be a unit which is able to be preassembled, which is added onto the housing so that the sensor system is inserted into the sensor compartment. Here, also, by means of a unit which is able to be preassembled, the assembly of the air supply device is simplified and therefore configured in a more economical manner. In addition, the air mass sensor can fulfil a flow-directing function, e.g. can bring about a flow deflection. For this, a corresponding guide contour or respectively deflection contour can be provided in the air mass sensor, in order to realize this guidance or respectively deflection of the flow with as little flow resistance as possible. Such a contour cannot be realized, or can only be realized with considerably increased effort, in the housing itself, so that the shifting of this guidance- or respectively deflection function into the sensor leads to a simplification. 
         [0019]    According to another advantageous further development, the air mass sensor can have a closure section, which closes a sensor compartment opening provided on the housing, through which the sensor system is inserted into the sensor compartment. Here, also, the functional density of the air mass sensor is increased, such that at the same time the installation effort is reduced, because with the mounting of the air mass sensor on the housing at the same time the sensor compartment opening, which is present for the insertion of the sensor system, can be closed. 
         [0020]    In another advantageous further development, provision can be made that the closure section is connected by a clip connection with the housing. Through the elimination of separate fastening elements, the assembly is simplified. 
         [0021]    For the supercharging of the fresh air, the internal combustion engine can be equipped with an exhaust gas turbocharger, the supercharger of which is incorporated into a fresh air system of the internal combustion engine, and the turbine of which is incorporated into an exhaust gas system of the internal combustion engine. The fresh air supply device which is presented here forms at least a component part of this fresh air system. In particular, the fresh air system of the internal combustion engine is formed by the fresh air supply device which is presented here. Accordingly, the supercharger of the exhaust gas turbocharger can also form a component part of the fresh air supply device. As the supercharger is integrated into the exhaust gas turbocharger, the exhaust gas turbocharger with its turbine can also form a component part of the fresh air supply device. Expediently, the fresh air path is directed within the fresh air supply device so that filtered fresh air is supplied to the supercharger, so that the supercharger is arranged in the fresh air path between the filter element and the charge air cooler. 
         [0022]    According to an advantageous embodiment, an inlet connection piece can be formed integrally on the housing, to which the supercharger is connected or able to be connected on the outlet side. Additionally or alternatively, an outlet connection piece can be formed integrally on the housing, which is connected or able to be connected to the supercharger on the inlet side. This outlet connection piece can open here on the inlet side directly into the previously mentioned sensor compartment, so that the fresh air flows, after the filter element, firstly through the sensor compartment and thereafter arrives at the supercharger. 
         [0023]    As mentioned above, according to an advantageous embodiment the charge-air cooler can have a cover body which closes the cooler compartment opening. In a simple case, this cover body can be configured as a cover plate which can consist in particular of a solid material. In an alternative embodiment, the cover body can be configured as a distributor- and collection box. The cover body is then a hollow body or respectively a housing for the coolant guidance. In both cases, provision is made that the coolant inlet and the coolant outlet are arranged or respectively constructed on this cover body. 
         [0024]    According to an advantageous embodiment, the charge-air cooler can have a plurality of plates which are stacked on one another in a stacking direction and which are spaced apart from one another in the stacking direction, wherein intermediate spaces are produced between adjacent plates in the stacking direction, which form a part of the charge air path. In other words, through the structure of the charge-air cooler which is proposed here, the charge-air path can be directed through the charge-air cooler through the intermediate spaces of the plates. As these plates are coupled with the coolant path in a heat-transferring manner, a contacting with the charge air over a large area can be realized via the plates, which enables as large a heat transmission as possible. 
         [0025]    According to an advantageous further development, the charge-air cooler can have several U-shaped tubes, the rectilinear sections of which are inserted through apertures of the plates, which are aligned to one another in the stacking direction, whilst curved sections of the tubes, which connect in each case two rectilinear sections with one another, run outside the stack. Hereby, a structure is produced for the charge-air cooler which is able to be realized in a particularly simple manner. In particular, only one stack of the said plates must be produced, into the apertures of which, which are aligned to one another, the U-tubes are inserted. The open ends of the U-tubes can communicate with a distributor chamber of the cover body or respectively with a collection chamber of the cover body. 
         [0026]    In an advantageous further development, the plates can be arranged loosely with respect to the tubes. In particular, hereby a soldering of the tubes with the plates is dispensed with, whereby the production of the charge-air cooler is able to be realized particularly economically. Expediently, a push fit is formed between the plates and the tubes in the respective apertures, which can have in particular a small play or even a press fit. 
         [0027]    In another advantageous further development, the straight sections of the tubes can be inserted through openings of a holding plate which adjoins the stack in the stacking direction and which is coated with an elastomer. In the mounted state, this holding plate can form the cover body or at least a component part of the cover body, which in the installed state closes the cooler compartment opening. 
         [0028]    In another advantageous further development, provision can now be made to provide the holding plate with a housing seal which seals a section of the cover body of the charge-air cooler, configured as distributor- and collection box, with respect to the housing, wherein the cover body or respectively the said section has the coolant inlet and the coolant outlet. In particular, the coolant inlet communicates with a distributor compartment of the distributor- and collection box, whilst the coolant outlet communicates with a collection compartment of the distributor- and collection box. In particular, the holding plate closes the distributor- and collection box in the region of the cooler compartment opening of the housing. The housing seal is preferably produced from a plastic. It can be formed in particular by an integral component part of the elastomer coating of the holding plate. 
         [0029]    According to an advantageous further development, the holding plate can have a tube seal for each of its openings, which seals the respective inserted section of the respective tube with respect to the holding plate. Hereby, a sufficiently tight guidance for the coolant can be realized within the charge-air cooler, also for the case where no soldered connection is provided between the holding plate and the tubes. The tube seals are preferably produced from a suitable plastic. They can be formed in particular by integral components of the elastomer coating of the holding plate. 
         [0030]    According to another embodiment, provision can be made that the sections of the tubes are subsequently widened mechanically exclusively in the region of the holding plates. By means of such a mechanical widening, the tubes can be fixed to the holding plate. At the same time, a radial gap between the tubes and the holding plate within the respective opening can be reduced or respectively eliminated. In so far as in addition a tube seal is provided, through the subsequent widening a prestressed radial abutment, in particular a radial pressing between the respective tube and the associated tube seal can be realized. 
         [0031]    In another advantageous embodiment, the housing can have a separate receiving pocket for each curved section, into which the respective curved section projects. Through this structural form, a positioning or respectively fixing in position is produced for the charge-air cooler in the housing on a side lying opposite the cooler compartment opening. At the same time, a guiding effect is produced for the assembly, whereby the insertion of the charge-air cooler into the housing is facilitated. 
         [0032]    According to another advantageous embodiment, the cover body of the charge-air cooler can have a clipped connection with the housing. Through this measure, separate fastening elements are dispensed with, which simplifies the assembly. 
         [0033]    In another embodiment, provision can be made that the filter element has at least one positioning element which cooperates with a positioning contour arranged on the housing in the filter compartment for the positioning and/or holding of the filter element in a predetermined relative position to the housing. Hereby, an incorrect assembly can be prevented. In particular, in the case of annular filter elements, the filter body of which consists of a folded web-shaped filter material, an increased reliability for the air mass measurement can be achieved by a connecting region of the filter body, in which end folds of the folded filter material are fastened to one another, are always arranged in the same relative position with respect to the respective positioning element, whereby downstream of the filter element always the same flow conditions occur. As an air mass sensor is usually arranged downstream of the filter element and preferably proximally thereto, likewise no change to the flow conditions occur there, so that the measurements of the air mass sensor also have substantially a consistent performance or respectively quality in the case of a changeover of filter element. In particular, through this measure, a readjustment of the air mass sensor can be dispensed with, which would be necessary per se in the case of a changeover of filter element if the air mass sensor is to continue to provide reliable measured values. 
         [0034]    According to a preferred further development, the filter element can therefore have an annular filter body and two end plates which are arranged on axial front faces of the filter body, wherein the respective positioning element is arranged on such an end plate. In particular, such a positioning element can be provided on each end plate. Through the arrangement on the end plate, the production can be realized particularly economically. In particular, the positioning elements can be formed integrally on the end plates. 
         [0035]    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. 
         [0036]    It shall be understood that the features mentioned above and to be explained in further detail 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. 
         [0037]    Preferred example embodiments of the invention are illustrated in the drawings and are explained in further detail in the following description, wherein identical reference numbers refer to identical or similar or functionally identical components. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0038]    There are shown, respectively diagrammatically, 
           [0039]      FIG. 1  a schematic diagram of an internal combustion engine, in the manner of a circuit diagram, 
           [0040]      FIG. 2  an isometric view of an internal combustion engine with fresh air system and exhaust gas system, 
           [0041]      FIG. 3  an exploded illustration of a fresh air supply device, 
           [0042]      FIG. 4  an exploded illustration of a charge-air cooler, 
           [0043]      FIG. 5  a longitudinal section of the charge-air cooler, 
           [0044]      FIG. 6  an enlarged detail view VI of  FIG. 5 , 
           [0045]      FIG. 7  an enlarged detail view VII of  FIG. 5 , 
           [0046]      FIG. 8-11  side views of the charge-air cooler in different embodiments, 
           [0047]      FIG. 12  an enlarged view of a detail XII in  FIG. 5  in installed state, 
           [0048]      FIG. 13  an isometric view of the fresh air supply device in the region of a mounted air mass sensor, 
           [0049]      FIG. 14  an isometric view of the air mass sensor, 
           [0050]      FIG. 15  an isometric view of the fresh air supply device in the region of the charge-air cooler with cut-open housing and truncated charge-air cooler, 
           [0051]      FIG. 16  an exploded, isometric view of the fresh air supply device in the region of a throttle device, 
           [0052]      FIG. 17  a view as in  FIG. 16  with mounted throttle device. 
       
    
    
     DETAILED DESCRIPTION 
       [0053]    According to  FIG. 1 , an internal combustion engine  1 , which is preferably used in a motor vehicle, comprises an engine block  2 , which contains combustion chambers  3  in cylinders which are not designated in further detail. The internal combustion engine comprises a fresh air system  4  for the supply of the combustion chambers  3  with fresh air. In addition, the internal combustion engine  1  is equipped with an exhaust gas system  5  for discharging exhaust gas from the combustion chambers  3 . The internal combustion engine  1  is supercharged and for this has an exhaust gas turbocharger  6 , which has in a conventional manner a supercharger  7  and a turbine  8 . The supercharger  7  is integrated into the fresh air system  4 . The turbine  8  drives the supercharger  7  and is integrated into the exhaust gas system  5 . 
         [0054]    The fresh air system  4  comprises an air filter device  9 , which is connected via a first connection  10  with an inlet of the supercharger  7 , so that filtered fresh air with environmental temperature arrives at the supercharger  7 . A second connection  11  connects an outlet side of the supercharger  7  with a charge-air cooler  12 , whereby hot charge air arrives at the charge-air cooler  12 . In the second connection  11  a throttle device  13  can be arranged. A third connection  14  connects the charge-air cooler  12  with the engine block  2 , so that cooled charge air arrives at the combustion chambers  3 . 
         [0055]    The charge-air cooler  12  is integrated into a charge-air cooling circuit  15 , which has a coolant pump  16  and a cooler  17 , which is able to be acted upon by an air stream  18 . In a vehicle application, this air stream  18  can be generated or respectively intensified by the headwind or by a fan which is not shown here. In  FIG. 1 , a rectangular frame  19  indicates a cold side of the internal combustion engine  1  with respect to the gas supply. A rectangular frame  20  indicates a hot side of the internal combustion engine  1  with respect to the gas elimination. Whilst in particular the air filter device  9 , the throttle device  13  and the charge-air cooler  12  are situated on the cold side  19 , in particular the supercharger  7 , the turbine  8  and preferably the entire exhaust gas system  5  are arranged on the hot side  20 . 
         [0056]    For cooling the engine block  2  in addition an engine cooling circuit  21  is provided, which contains a coolant pump  22  and a cooler  23 . This cooler  23  can also be acted upon by an air stream  24 , which can be formed by the headwind and intensified by a fan, which is not shown. A thermostatic valve  25  enables a switchover between a warmup operation bypassing the cooler  23  and a cooling operation integrating the cooler  23 . As can be seen, the two cooling circuits  15 ,  21  are configured separately. They can be combined with one another insofar that for example the two coolers  17 ,  23  are arranged directly one behind the other, in order to be able to act upon them with a shared air stream  18  or respectively  24 , whereby in particular only one shared fan is to be provided. Through the separation of the two cooling circuits  15 ,  21  it is possible in particular to operate the two cooling circuits  15 ,  21  at different temperature levels. In particular, the charge-air cooling circuit  15  is operated at a lower temperature level than the engine cooling circuit  21 . 
         [0057]    According to  FIG. 2 , the fresh air system  4  comprises an air supply device  26 , to which in particular the exhaust gas turbocharger  6  and a charge-air distributor  27  can be added, which represents for example the third connection  14 . The exhaust gas system  5  comprises an exhaust gas collector  28 , which leads to the turbine  8 . Downstream of the exhaust gas turbocharger  6 , the exhaust gas system  5  can contain for example an oxidation catalyst  29 , a particle filter  30  and a sound absorber  31 . The coolant pump  16  of the charge-air cooling circuit  15  can also be added on to the air supply device  26  and can then be included in the scope of the air supply device  26 . 
         [0058]    In  FIG. 2  the engine block  2  has, purely by way of example, only three cylinders, whilst in  FIG. 1  four cylinders are provided. In  FIG. 2 , an arrow  32  indicates a direction of travel of the vehicle, whereby a preferred installation position for the internal combustion engine  1  is to be indicated. In addition, in  FIG. 2  a rectangular frame  33  indicates the assembly group of the fresh air supply device  26 , which is explained in further detail below. As can be seen, the air supply device  26  is configured so that very short paths are realized between the cold side and the warm side of the internal combustion engine  1 , so that additional ducts and hoses can be dispensed with. The arrangement of the charge-air cooler  12  takes place in the housing  34  preferably so that the hot charge air can already be cooled very early, i.e. after a very short flow path. Hereby, the hot side of the fresh air path becomes comparatively short, which reduces the thermal stress of the fresh air supply device  26  and in particular the thermal stress of subsequent structural parts and components, such as e.g. the throttle device  46 , in the air flow direction. 
         [0059]    In accordance with  FIG. 3 , the fresh air supply device  26  has a one-piece housing  34 , which contains integrally a filter compartment  35  and a cooler compartment  36 , which are separated from one another by a base  89 . The base  89  is likewise an integral component of the housing  34 . It can be reinforced by webs. The fresh air supply device  26  comprises in addition a filter element  37 , which is able to be inserted into the filter compartment  35 . Furthermore, a cover  38  is provided, which can close a filter compartment opening  39  of the housing  34 . Through this filter compartment opening  39  the filter element  37  is able to be inserted into the filter compartment  35 . By closing the filter compartment opening  39  with the cover  38 , the air filter device  9  introduced in  FIG. 1  is realized, and namely as an integral component of the fresh air supply device  26 . In particular, the cover  38  can have a clipped connection with the housing  34 , so that separate fastening elements can be dispensed with. Through the clipped connection, the cover  38  is fastened on the housing  34  so as to be able to be detached at any time. 
         [0060]    In the preferred embodiment shown in  FIG. 3 , the filter element  37  is configured as a ring filter element, so that it has an annular filter body  92  and two end plates  93 ,  94 . The filter body  92  surrounds an interior space and consists preferably of a pleated or respectively folded web-shaped filter material. The end plates  93 ,  94  are arranged on axial front faces of the filter body  92 . In the example, the end plate  93  arranged on the left in  FIG. 3  is configured as a closed end plate  93 , whereas the end plate  94  arranged on the right is configured as an open end plate  94 . The open end plate  94  contains a central opening  95 , through which a fluid connection with an interior of the filter element  37 , surrounded by the filter body  92 , is possible. On the open end plate  94  in addition an axially protruding radial seal  97  is formed, which surrounds the opening  95  and in the installed state lies in a radially sealing manner against a connection piece of the housing  34  projecting into the opening  95 . Basically, an embodiment with two open end plates  93 ,  94  is also conceivable. The filter element  37  is configured in addition with at least one positioning element  90 . In the example, two positioning elements  90  are provided. In each case a positioning element  90  is arranged in each case on one of the end plates  93 ,  94 . Preferably, the respective positioning element  90  is formed integrally on the respective end plate  93 ,  94 . The positioning elements  90  cooperate with positioning contours  91  complementary thereto on insertion of the filter element  37  into the filter compartment  35 , in order to position the filter element  37  relative to the housing  34  in a predetermined relative position. In the installed state, the positioning elements  90  can cooperate in addition for holding or respectively fixing this relative position between filter element  37  and housing  34 . In the example, the respective positioning element  90  is configured as a rectilinear bar which extends transversely and eccentrically to the longitudinal centre axis of the filter element  37  and projects on both sides over the associated end plate  93 ,  94 . 
         [0061]    In other embodiments, instead of the preferred annular filter element  37  any other desired filter element  37  can also be used, which has for example e.g. a plate-shaped or horseshoe-shaped filter body. 
         [0062]    The air supply device  26  comprises in addition the charge-air cooler  12 , which is able to be inserted through a cooler compartment opening  40  into the cooler compartment  36 . For this, the charge-air cooler  12  can be inserted into the cooler compartment  36  through the cooler compartment opening  40 . Expediently, the charge-air cooler  12  has a cover body  41 , which closes the cooler compartment opening  40  in the installed state. 
         [0063]    In addition, the housing  34  has integrally a fresh air inlet  42  for unfiltered fresh air and a charge-air outlet  43  for cooled charge air. The charge-air distributor  27  is able to be connected to the charge-air outlet  43 . 
         [0064]    The housing  34  contains in addition a throttle compartment  44 , into which a throttle member  45  of a throttle device  46  is able to be inserted. The throttle compartment  44  is formed here integrally on the housing  34 . The throttle compartment  44  is situated in addition with respect to a fresh air path, which leads through the housing  34 , between the charge-air cooler  12  and the charge-air outlet  43 . 
         [0065]    The housing  34  contains in addition a sensor compartment  47 , into which a sensor system  48  of an air mass sensor  49  is able to be inserted. The sensor compartment  47  is also formed integrally on the housing  34 . It is situated in the fresh air path between the filter compartment  35  and an outlet connection piece  50 , which is likewise formed integrally on the housing  34 . An inlet  51  of the supercharger  7  is able to be connected to this outlet connection piece  50 . On the other hand, an outlet  52  of the supercharger  7  is able to be connected to an inlet connection piece  53 , which is formed integrally on the housing  34 . The inlet connection piece  53  is arranged here with respect to the fresh air path upstream of the charge-air cooler  12  or respectively upstream of the cooling compartment  36 . 
         [0066]    In order to be able to produce the housing  34  in a particularly simple manner as a one-piece injection moulded part, several housing openings are oriented parallel to one another. For example, the cooler compartment openings  40 , the charge-air outlet  43 , the outlet connection piece  50  and the inlet connection piece  53  are oriented parallel to one another. In addition, the fresh air inlet  42  and a sensor compartment opening  57  are oriented parallel to one another here. The three groups which are provided here, which contain respectively housing openings parallel to one another, are aligned to one another in the example in three spatial directions oriented perpendicularly to one another. 
         [0067]    As can be seen from  FIGS. 3 ,  16  and  17 , the throttle device  46  can expediently be a unit which is able to be preassembled, which can be added onto the housing  34  so that in so doing the throttle member  45  is inserted into the throttle compartment  44 . Expediently, the throttle device  46  has a closure section  54 . For the insertion of the throttle member  45 , the housing  34  has a throttle compartment opening  55 , through which the throttle member  45  is able to be inserted into the throttle compartment  44 . The closure section  54  closes this throttle compartment opening  55  in assembled state. Expediently, a clip connection  56  can be provided for securing the throttle device  46  to the housing  34 . In the example, the clip connection  56  comprises detent elements on the housing side, which engage behind the closure section  54 . On a side facing the throttle compartment opening  55  in accordance with  FIG. 16  expediently an axial seal  98  can be arranged on the closure section  54 , which in the installed state lies in a sealing manner along the opening edge of the throttle compartment opening  55  on the housing  34 . In addition, a further deal  99  can be arranged on an outer side of the frame  100 , which in the installed state engages into a guide groove  101  which is formed on an inner side of the housing  34  exposed to the throttle compartment  44 . The frame  100  surrounds the throttle member  45 , which is configured as a valve, in particular as a butterfly valve, in order to provide the sealing contour required for this on the throttle device  46  itself, whereby a highly efficient and relatively precisely modulable throttling is able to be realized. 
         [0068]    According to  FIGS. 3 ,  13  and  14 , the air mass sensor  49  preferably forms a unit which is able to be preassembled, which can be added onto the housing  34  so that in so doing the sensor system  48  is inserted into the sensor compartment  47 . In order to be able to insert the sensor system  48  into the sensor compartment  47 , a sensor compartment opening  57  is provided on the housing  34 . The air mass sensor  49  has a closure section  58 , which is shaped in a complementary manner to the sensor compartment opening  57 , so that through the mounting of the air mass sensor  49  the sensor compartment opening  57  is automatically closed. Here, also, in accordance with  FIG. 13  a clip connection  59  can be provided, in order to be able to fix the air mass sensor  49  on the housing  34  in a simple manner. In the example, the clip connection  59  comprises several detent arms on the housing side, which in the assembled state overlap the closure section  58 . 
         [0069]    According to  FIG. 14 , a seal  60  can be arranged on an inner side of the closure section  58  facing the housing  34 , in order to simplify a gas-tight closing of the sensor compartment opening  57  by means of the closure element  58 . A corresponding seal can also be arranged on the inner side of the closure section  54  of the throttle device  46  facing the housing  34 . In  FIG. 14  in addition a guide contour  96 , formed on the air mass sensor  49 , can also be seen, which on mounting of the air mass sensor  49  penetrates into the sensor compartment  47  and is positioned therein so that the desired flow deflection or respectively flow guidance is produced therein. In the example, by means of the guide contour  96  in the sensor compartment  47  a flow deflection about approximately 90° is achieved with comparatively little flow resistance. 
         [0070]    A preferred embodiment of the charge-air cooler  12  with variants is explained in further detail by means of  FIGS. 4-12  and  15 . 
         [0071]    The charge-air cooler  12  has a cover body  41 , which in the assembled state tightly closes the cooler compartment opening  40 . This cover body  41  has here a coolant inlet  61  and a coolant outlet  62 . Therefore, the coolant inlet  61  and coolant outlet  62  are situated on an outer side of the housing  34 . Coolant inlet  61  and coolant outlet  62  are connected with one another within the charge-air cooler  12  by a coolant path. The charge-air cooler  12  is able to be integrated into the charge-air cooling circuit  15  via the connections  61 ,  62 . 
         [0072]    In an embodiment which is not shown, the cover body  41  can basically be configured as a simple cover plate which has no flow guidance function in its interior. However, the embodiment which is shown here is preferred, in which the cover body  41  has a distributor- and collection box  63  or is configured as such. According to  FIGS. 5 and 8 , this distributor- and collection box  63  can therefore have in particular a distributor chamber  64 , which is fluidically connected with the coolant circuit  61 , and a collection chamber  65 , which is fluidically connected with the coolant outlet  62 . 
         [0073]    According to  FIGS. 4-7 , the charge-air cooler  12  comprises a plurality of plates  66 , which are stacked on one another in a stacking direction  67 . According to  FIG. 7 , an intermediate space  68  is formed respectively between individual plates  66 , which are adjacent to one another in the stacking direction  67 . These intermediate spaces  68  form a portion of the charge-air path which leads through the charge-air cooler  12  within the housing  34 . 
         [0074]    The charge-air cooler  12  has in addition several U-shaped tubes  69 , which have respectively two rectilinear sections  70  and one curved section  71 , wherein the respective curved section  71  connects the two associated rectilinear sections  70  fluidically with one another. In addition, the rectilinear sections  70  expediently extend parallel to one another, so that the curved section  71  forms a 180° arc. The rectilinear sections  70  are inserted through apertures  72 , which are formed in the plates  66 . In adjacent plates  66 , these are arranged aligned to one another by breaks  72  in the stacking direction  67 . The plates  66 , stacked on one another, form a plate stack  73 . Whilst the rectilinear sections  70  of the tubes  69  therefore run largely within the plate stack  73 , the curved sections  71  extend outside the stack  73 . According to  FIGS. 6 and 7 , the apertures  72  can have respectively a turn  74 . A height of the turns  74  measured in the stacking direction  67  defines the distance, measured in the stacking direction  67 , of adjacent plates  66 . At the same time, the turns  74  simplify the assembly of the charge-air cooler  12 . 
         [0075]    In  FIG. 4 , purely by way of example next to the plate stack  73  an individual plate  66  is illustrated, and next to the arrangement of the tubes  69  an individual tube  69  is illustrated. 
         [0076]    An embodiment is particularly advantageous in which the plates  66  are arranged loosely with respect to the tubes  69 , so that therefore in particular no soldered connections are present between the plates  66  and the tubes  69 . For this purpose, the turns  74  can respectively define a push fit or press fit. 
         [0077]    In the embodiments which are shown here, the cover body  41  has a holding plate  75 , which closes the distributor- and collection body  63  towards the stack  73  and which contains a plurality of openings  76 . The free ends or end sections  80  of the straight sections  70  of the tubes  69  are inserted through these openings  76 . The holding plate  75  is expediently coated with an elastomer  77 . This elastomer coating, which is likewise designated below by  77 , is expediently realized so that it covers the holding plate  75  completely on a side facing the chambers  64 ,  65  of the distributor- and collection box  63 . Furthermore, the elastomer coating  77  is additionally configured here so that it penetrates and engages behind the openings  76  according to  FIG. 6 . Finally, provision is made according to  FIG. 12  that the elastomer coating  77  forms a circumferential housing seal  78  on the holding plate  75 , which surrounds a circumferential outer edge  79  of the holding plate  75  in a closed manner in the circumferential direction and in so doing also overlaps the edge  79  on both sides. The side of the holding plate  75  facing the stack  73  is largely uncoated in the example. 
         [0078]    According to  FIG. 6 , the tubes  69  or respectively the rectilinear sections  70  thereof are in contact with the elastomer coating  77  in the openings  76 , whereby a sufficient seal can be realized. In addition, to improve the seal and for fixing the holding plate  75  on the stack  73 , provision can be made to mechanically widen with regard to their cross-section the ends  80  of the tubes  69  inserted into the holding plate  75 , in accordance with a double arrow  81 . Hereby, a fixing of the tubes  69  on the holding plate  75  can be realized, whereby the entire stack  73  is stabilized with respect to the holding plate  75 . It is noteworthy here that no soldered connection is required for stabilizing the stack  73 . At the same time, the pressing of the tube ends  80  in the openings  76  of the holding plate  75  improves the seal of the elastomer layer  77 . 
         [0079]    The elastomer layer  77  therefore forms on the holding plate  75  a tube seal  82  for each opening  76 , which seals the respective inserted end section  80  of the respective tube  69  with respect to the holding plate  75 . In addition, the elastomer layer  77  forms the housing seal  78 , which in the assembled state seals the distributor- and collection box  64  or respectively the entire cover body  41  with respect to the housing  34 . The housing seal  78  engages here axially respectively into a groove  84  on the housing side and a groove  85  on the box side. Furthermore, according to  FIG. 5  the elastomer layer  77  in connection with a dividing wall  87  of the distributor- and collection box  63  seals the distributor compartment  64  of the distributor- and collection box  63  on the inlet side with respect to the collection compartment  65  of the distributor- and collection box  63  on the outlet side. 
         [0080]    According to  FIG. 12  the cover body  41  can be fastened to the housing  34  by means of a clip connection  83 . In the example which is shown here, several clip elements are provided on the housing side, which engage behind a circumferential edge of the cover body  41 , which is formed here on the distributor- and collection box  63 . 
         [0081]    According to  FIG. 15 , the housing  34  can have respectively a separate receiving pocket  86  on a side lying opposite the cooler compartment opening  40  for each curved section  71 , which receiving pocket is open to the interior of the housing  34  and into which the respective curved section  71  projects. Hereby, an efficient fixing in position in the housing  34  is produced for the charge-air cooler  12  via the tubes  69 . 
         [0082]    With reference to  FIGS. 8-11 , four variants for the charge-air cooler  12  are to be explained below in further detail, wherein principally the guiding of coolant in distributor- and collection box  63  is addressed. 
         [0083]      FIG. 8  shows the simple embodiment, presented here in further detail, in which a single distributor compartment  64  and a single collection compartment  65  are formed in the distributor- and collection box  63 . These are separated from one another according to  FIG. 5  by a dividing wall  87  formed integrally on the box  63 , which dividing wall in the installed state comes to lie on the front face against the elastomer layer  77 . 
         [0084]      FIGS. 9-11  now show three different variants of the embodiment shown in  FIG. 8 , wherein for simplified understanding the distributor- and collection box  63  is illustrated so as to be transparent.  FIG. 9  shows an embodiment in which a further dividing wall  88  is arranged in the box  63 , whereby the two chambers  64 ,  65  of the embodiment shown in  FIG. 8  are divided into a total of four chambers, so that consequently a first inlet chamber  64  and a second inlet chamber  64 ′ are present, which are fluidically connected with two coolant inlets  61 ,  61 ′. Accordingly also two outlet chambers  65  or respectively  65 ′ are provided, which are connected with two coolant outlets  62 ,  62 ′. Hereby, in particular a double-flow low temperature cooler can be realized. 
         [0085]    In the embodiment shown in  FIG. 10 , the inlet chamber  64  is provided with a zigzag contour in the box  63 , in order to connect different tubes  69  with one another via different sections. The inlet chamber  65  then connects the remaining tube sections with one another in a manner complementary thereto. Through this arrangement, a comparatively homogeneous temperature distribution can be realized within the charge-air cooler  12 . 
         [0086]    In the embodiment shown in  FIG. 11 , again four chambers are formed in the box  63 , but connected differently to in  FIG. 9 , whereby it is possible to realize in the charge-air cooler  12  a low temperature circuit formed for example in the left-hand half and a high temperature circuit formed for example in the right-hand half.