Abstract:
System housing, in particular for a heating, ventilating and/or air-conditioning system of a vehicle, comprising at least three housing parts, which serve for accommodating air-conditioning-system components and/or for forming air-channeling paths, one of the housing parts comprising a first abutment surface and a second abutment surface, up to which the other two housing parts can be advanced in each case parallel to a normal vector of the abutment surface which is advanced up in each case.

Description:
BACKGROUND OF THE INVENTION 
   The present invention relates to a system housing, in particular for a heating, ventilating and/or air-conditioning system of a vehicle, comprising at least three housing parts, which serve for accommodating air-conditioning-system components and/or for forming air-channeling paths, as described by the preamble of the independent claim. 
   System housings for heating, ventilating and/or air-conditioning systems are usually provided by injection molding in the prior art. In the design, the person skilled in the art has to ensure, inter alia, that the housing has a high level of sealing and that the number of steps required for assembly purposes is as small as possible. 
   Up until now, housings have usually been provided by two injection moldings. In this case, one injection molding is a bottom or base part and the other is a top or head part and a central part. These are brought into abutment with one another and connected by means of screw connection or the like. The reason for subdividing the housing into two parts is based on the fact that the system housing is to have the fewest possible connections to the surrounds, on the one hand, in order for it to be possible to provide the necessary level of sealing and also in order for it to be possible to ensure the necessary rigidity and vibration resistance. 
   The disadvantage here is that air-directing elements, in particular air flaps, usually take a lot of time to install in the system housing since the shapes are too complex, or are not possible to reproduce, for injection molding. The installation of the additional elements here gives rise to high assembly and maintenance outlay. The poor internal sealing between the housing parts and the plugged-in air-directing elements is a further disadvantage. 
   The object of the invention is thus to provide a system housing which is easier, quicker and thus more cost-effective to produce and assemble and which ensures sufficient levels of sealing, stability and vibration resistance for the housing parts. 
   This object is achieved by the features of the independent patent claim, expedient developments being described by the features of the dependent claims. 
   BRIEF SUMMARY OF THE INVENTION 
   The present invention proposes, in particular, a system housing, in particular for a heating, ventilating and/or air-conditioning system of a vehicle, comprising at least three housing parts, which serve for accommodating system components and/or for forming air-channeling paths, one of the housing parts comprising a first abutment surface and a second abutment surface, up to which the other two housing parts can be advanced in each case essentially parallel to a normal vector of the respective abutment surface. 
   The basic idea of the present invention is to divide up a complex system housing into geometrical housing parts such that essentially all the functional units, for example air channels, air flaps and the like, can be provided by means of just one process step. It is only during a subsequent assembly operation that the housing parts are connected to one another such that they engage one behind the other and are torsionally rigid. 
   The abutment surfaces here are conceived of essentially as planes, it also being possible for integrally formed air-directing elements, stiffening elements and connecting devices to project out of the planes. These are guided into corresponding recesses of the other housing parts and thus also increase the torsional rigidity of the system housing overall. 
   During assembly, in the first instance, one housing part is advanced up to the housing part with the two abutment surfaces, the parallel direction of advancement also allowing the formation of housing parts which project far out of the surface, and connected to this housing part, for example, by means of screw connections or the like. In a further step, at least one further housing part is advanced up to the further abutment surface, in which case it is possible for it to be connected not just to the adjacent housing part. 
   The normal vectors advantageously run essentially parallel. It is thus straightforwardly possible to provide easy assembly in a single plane. 
   Furthermore, it is advantageous if at least the housing part with the two abutment surfaces is constructed from a first portion and a second portion. These housing parts may already provide air channels with the corresponding components, e.g. air flaps. This makes it possible to reach, during assembly, connecting devices which are located within the housing. 
   It is additionally advantageous if the portions can be brought into engagement at right angles in relation to the direction of advancement of the two housing parts. It can thus be ensured that the greatest possible amount of installation space is available for the adjacent components and that, during installation of the system housing, all that has to be ensured is that the space above the portions remains freely accessible. 
   It is advantageous if at least the housing part with the two abutment surfaces is constructed from an essentially u-shaped portion and from an essentially t-shaped portion. 
   The t-shaped portion can be introduced into the u-shaped portion such that the u-shaped portion is subdivided into two air channels, so that air channels can easily be provided for associated air-conditioning zones in the vehicle interior. In a preferred embodiment, it is also the case that the line of symmetry of the at least three housing parts in the assembled state lies along the leg of the t-shaped portion. 
   The housing parts and/or portions advantageously comprise air-directing elements, in particular air flaps. The person skilled in the art is aware of a large number of air-flap shapes and forms or further air-directing elements. It is possible here for the air flaps even to be provided with stiffening struts or the like in order to increase the stability of the system housing. 
   Furthermore, it is advantageous if sealing lips are provided on the housing parts and/or portions. Sealing lips can easily be integrally formed, for example, by means of so-called two-component injection molding. 
   It is additionally advantageous if screw connections, latching connections and tongue/groove connections are provided on the housing parts and/or portions. A combination of screw connections, latching connections and tongue/groove connections can be used to provide the necessary level of sealing for the system housing. 
   The housing parts and/or portions are advantageously undercut-free injection moldings in each case. 
   The housing parts can be provided easily, quickly and cost-effectively by means of injection molding. Those parts which have to be of movable configuration can be provided, for example, by means of so-called film-hinge technology or the like. Flexible parts, for example sealing lips, may be provided by means of two-component injection molding. 

   
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
     Further features and advantages of the invention will become clearer on reading the following description of a preferred embodiment, which is given merely by way of example, is not intended to be restrictive in any way and is provided with reference to the attached drawings, in which: 
       FIG. 1  shows a perspective illustration of three housing parts of a system housing according to the invention prior to assembly; 
       FIG. 2  shows a perspective view of the central housing part from  FIG. 1 , in the non-assembled state but with air flaps already mounted; 
       FIG. 3  shows the central housing part  2  from  FIG. 2  turned through 180°, in the non-assembled state; 
       FIG. 4  shows the central housing part from  FIG. 2 , the portions having been assembled; 
       FIG. 5  shows a front view of a system housing according to the invention; and 
       FIG. 6  shows a perspective view of the system housing from  FIG. 5 . 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   The embodiment which is shown in the figures illustrates a system housing, or parts thereof, for a so-called four-zone air-conditioning system of a motor vehicle. This system provides four independent air-conditioning zones in the vehicle interior. 
     FIG. 1  shows a perspective illustration of a first housing part  1 , a second housing part  2  and a third housing part  3  of a system housing according to the invention prior to assembly. The housing parts  1 ,  3  are produced essentially in one piece in each case by means of injection molding. The first housing part  1  here is designed as a left-hand air-distributor housing, the second housing part  2  is designed as a central air-distributor housing and the third housing part  3  is designed as a right-hand air-distributor housing. 
   Air flaps  5 ,  6 ,  7 ,  8  are integrally formed on the housing parts  1 ,  2  and can be pushed into respective corresponding recesses  10 ,  11 ,  12  of the other housing parts  2 ,  3 . The flaps  5 ,  6 ,  7 ,  8  are mounted in a movable manner, for example, by means of a so-called shaft/hub connection. 
   It can clearly be seen in  FIG. 1  how the housing parts  1 ,  3  are advanced up to the central housing part  2  and can be brought into abutment therewith. Tongue/groove connections, stabilizing projections and screw-connecting bushings are integrally formed on the housing parts  1 ,  2 ,  3 . The combination of these means ensures a high level of sealing for the system housing. It is also possible, at critical connections, to form sealing lips on the housing parts  1 ,  2 ,  3  by means of so-called two-component injection molding. 
     FIG. 2  shows a perspective view of the central housing part  2  from  FIG. 1 . The central housing part  2  comprises an essentially u-shaped portion  20  and an essentially t-shaped portion  21 . The portions  20 ,  21  are likewise produced in one piece by means of injection molding. Air flaps  22 ,  23  are mounted on the u-shaped portion  20 . 
   It can clearly be seen in  FIG. 2  how the portions  20 ,  21  are displaced one inside the other, so that the u-shaped portion  20  is divided up into two air channels, each comprising an air flap  22 ,  23 , the central wall being provided by the t-shaped portion  21 . The portions  20 ,  21  are connected to one another in a sealed manner by means of screw connections or tongue/groove connections. 
     FIG. 3  shows the central housing part  2  from  FIG. 2  turned through 180°. It can clearly be seen in  FIG. 3  how the t-shaped portion  21  can be pushed into the u-shaped portion  20  to form two air channels. 
     FIG. 4  shows the central housing part  2  from  FIG. 2 , with the u-shaped portion  20  and t-shaped portion  21  connected. As can be seen in  FIG. 4 , the u-shaped portion  20 , rather than extending over the entire portion  21 , extends only over the top region of the latter. The region  25 , over which the u-shaped portion  20  does not extend, is covered over by the housing parts  1 ,  3 , so that air channels are also formed in this region. 
     FIG. 5  shows a front view of system housing  30  according to the invention. The abutment surfaces  31 ,  32  between the housing parts  1 ,  2 ,  3  have been emphasized. The housing parts  1 ,  2 ,  3  are connected to one another. It cannot be seen in  FIG. 5  that the housings  1  and  3  together form the housing for the heat exchanger. 
   The air channels  36 ,  37 ,  38 ,  39  formed by the housing parts  1 ,  2 ,  3  can be seen particularly clearly in  FIG. 5 . The essentially symmetrical construction of the housing parts  1 ,  2 ,  3  in the connected state is likewise clear to see. The line of symmetry here runs through the central housing part  2 . 
     FIG. 6  shows a perspective view of the system housing  30  from  FIG. 5 . The same parts are provided with the same designations here. This view shows air channels  40 ,  41  which are formed by the housing parts  1 ,  2 ,  3 , but were not clearly visible in the other figures. 
   The system housing  30  can be subdivided into two functional parts along the line of symmetry shown in  FIG. 5 . The left-hand part of the system housing  30  which is shown in  FIG. 6  here is assigned the left-hand part of a vehicle interior (not illustrated) and the right-hand part is correspondingly assigned the right-hand part of the vehicle interior. 
   The air channels  36 ,  37  serve for channeling mixed air into the rear left-hand and right-hand parts of the vehicle interior. The air channels  38 ,  39  serve for channeling mixed air into the front left-hand and right-hand parts of the vehicle. The air channels  40 ,  41  serve for channeling hot air for defrosting purposes,  42 / 44  rear footwell,  43 / 45  front footwell. 
   An additional advantage is that it is easily possible for the air-channeling housing as a whole to be assembled in layers without any need for the housing to be turned or rotated for this purpose. 
   A possible assembly sequence will be described by way of example. In a first step, the first or left-hand housing part is positioned in an assembly arrangement and fitted out with the components for the first housing part. The second or central housing part is then preassembled with corresponding components. In a further step, the third or right-hand housing part is fitted out. Furthermore, the first and second housing parts or the left-hand and central housing parts are connected to one another. The right-hand housing part is then mounted on the central housing part. Finally, the external components, for example motors and kinematics, are mounted on the right-hand housing part. 
   In general terms, the present solution can provide an easy-to-assembly system housing which, in contrast to the prior-art solutions, rather than being constructed with a minimum number of housing parts, has as many housing components as are required for all the necessary air channels with associated air-channeling elements to be provided in the production process. 
   The invention thus provides an easy- and quick-to-assemble system housing, in particular for heating, ventilating and/air-conditioning systems of a vehicle, which, in addition, satisfies the stringent requirements in respect of sealing, rigidity and vibration resistance.