Abstract:
A housing for a ventilation, heating, and/or air conditioning system of a motor vehicle, wherein the housing is made of multiple parts and forms at least one air flow path in the interior and optionally has at least one heat exchanger, whereby the housing has first regions and has second regions, whereby the first regions have a greater strength than the second regions.

Description:
[0001]    This nonprovisional application claims priority under 35 U.S.C. §119(a) to German Patent Application No. DE 10 2013 217 082.3, which was filed in Germany on Aug. 27, 2013, and which is herein incorporated by reference. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to a housing for a ventilation, heating, and/or air conditioning system of a motor vehicle, whereby the housing is made of multiple parts and forms at least one air flow path in the interior and optionally has at least one heat exchanger. 
         [0004]    2. Description of the Background Art 
         [0005]    The housing of an air conditioning system or a ventilation system takes over a number of tasks. In addition to guiding one or more fluid flows, such a housing routinely contains heat exchangers, which enable the temperature control of an air flow or a fluid flow. Further, such housings have an adjusting device for influencing a fluid flow. These include in particular valve elements. 
         [0006]    Many different embodiments for climate control system housings are known from the state of the art. The housings are designed such that they withstand stresses arising during operation without being damaged thereby. Ribbing, which reinforces especially stressed regions, is routinely provided for this purpose. Moreover, the housings have a substantially uniform wall thickness. 
         [0007]    It is especially disadvantageous in the solutions in the conventional art that the housings are routinely made of only one material. Furthermore, the housings routinely have only one uniform wall thickness, which is configured such that the housing walls bear up against the greatest arising stresses. This results in a high housing weight, which is disadvantageous particularly with respect to vehicle CO 2  emissions. 
       SUMMARY OF THE INVENTION 
       [0008]    It is therefore an object of the present invention to provide a housing for a ventilation, heating, and/or air conditioning system, the housing being optimized with respect to its durability and simultaneously having as low a weight as possible. 
         [0009]    An exemplary embodiment of the invention relates to a housing for a ventilation, heating, and/or air conditioning system for a motor vehicle, whereby the housing is made of multiple parts and forms at least one air flow path in the interior and has at least one heat exchanger, whereby the housing has first regions and second regions, whereby the first regions have a greater strength than the second regions. 
         [0010]    The housing refers in particular to the enclosure for the inner air flow paths, the valves, actuators, and the mounting for the heat exchanger disposed within the housing. The housing advantageously has openings through which one or more air flows can flow into the housing. In addition, openings are provided advantageously through which the air flow can again flow out of the housing, for example, after temperature control, mixing, or splitting. 
         [0011]    The housing has regions which are used mainly for guiding a fluid flow and regions which accommodate other components, or by which the housing is connected to surrounding structures of the vehicle. The regions that have bearing functions, and therefore contribute to the structural integrity of the housing, advantageously have a greater strength than regions that are used solely for fluid guidance or form simple partition walls. 
         [0012]    The first regions have greater wall thicknesses than the second regions. 
         [0013]    In order to achieve a greater strength, greater wall thicknesses can be provided advantageously. A weight-optimized housing can be produced via a wall thickness distribution tailored to the actually occurring stresses. Designing of the housing can occur similar to the method from metalworking known as “tailored blanks.” Smooth transitions between regions with a different material thickness are provided in this case. Likewise, a number of different materials can be used in one component. Preferably, the housing is made of a plastic. Forming the housing from a metallic material is also foreseeable, however. 
         [0014]    It is especially advantageous, if the wall thicknesses of the second regions are preferably more than 20%, thereby preferably more than 40%, and thereby preferably more than 60% smaller than in the first regions. 
         [0015]    A smaller wall thickness is particularly advantageous with respect to the total weight of the housing. A reduction of the wall thickness only in regions with a lower mechanical stress is advantageous in order not to have a negative effect on the stability of the housing. 
         [0016]    At least one air-guiding region of the housing can be formed by at least one film and/or by at least one fabric piece. 
         [0017]    The formation, for example, of an air channel or a partition wall of film or a fabric piece is especially advantageous, because extremely thin walls can be produced. This is helpful for the weight of the housing. Furthermore, there are more degrees of freedom with respect to the design of a wall from a film than in the case of an injected plastic. The films or fabric pieces can be provided advantageously with a binding agent and/or adhesive and/or a coating agent, as a result of which an air-tight binding or an air-tight structure can be produced. 
         [0018]    The film and/or fabric piece can be inserted in the housing and/or cast and/or injected and/or glued in the housing and/or back-injected in the housing. Advantageously, this results in a force-fitting and/or form-fitting connection. 
         [0019]    Films and/or fabric pieces can be advantageously inserted at the appropriate locations in the housing. To this end, for example, a temporary molding device can be provided, in which the appropriate elements can be placed. Alternatively, the films and/or fabric pieces with an adhesive, such as, for example, a synthetic resin, can be cast in the housing or back-injected in the housing. A fabric and/or film can also be advantageously injected into the housing. For this purpose, a molding device for shaping and positioning the film and/or fabric, is also provided advantageously in the manufacturing process. 
         [0020]    It is advantageous, moreover, for the housing to have a substantially uniform wall thickness, whereby additional reinforcing components are provided in the first regions. 
         [0021]    In order to design the regions experiencing greater mechanical stresses as sufficiently stable and, nevertheless, to keep the weight of the housing as low as possible, it can be provided advantageously that the entire wall thickness of the housing is reduced to a minimum and additional reinforcing components are provided only in the regions of greater mechanical stress. These can include, for example, fabric structures and/or films that are applied to the walls of the housing. 
         [0022]    The fabric can be formed of carbon fibers and/or glass fibers and/or plastic fibers. 
         [0023]    The fabrics are advantageously designed such that they have a sufficient strength and optionally are fluid-tight, in order to be able to realize their function, such as, for example, fluid guiding. Among others, aramid fibers can be used here, for example. 
         [0024]    It is especially advantageous for the reinforcing component to be formed of films and/or fabric pieces. 
         [0025]    The films and/or fabric pieces are advantageously glued to a region of the housing, sprayed onto it, or mounted on a housing region. In so doing, for example, a film mounted on support structures can form a very thin-walled fluid-guiding channel. 
         [0026]    The housing can be produced at least partially in an injection molding process. 
         [0027]    In the injection molding process, particularly housing parts made of plastic can be produced. It is especially advantageous if the housing parts have a wall thickness tailored to the stresses during operation. The housing parts fabricated of plastic advantageously can be reinforced by fabric structures and/or films or supplemented by them. Films and fabric structures can be used in particular in regions of low mechanical stress. 
         [0028]    It is especially advantageous for the first regions and/or the second regions to have concave and/or convex wall geometries. 
         [0029]    Concave and/or convex wall geometries are especially advantageous, because they are especially stable. In comparison with straight, smooth, flat regions, concavely or convexly curved regions are generally stable. It is especially advantageous, if the mechanically more greatly stressed regions have a concave or convex shape. Alternatively, stiffening can be carried out by beading or pockets, which can be formed on one side or also on alternating sides. These can be disposed, inter alia, in a first region. In this case, the wall thickness may also be reduced, whereby the introduced structures, such as beading or pockets or complementary beading or pockets nevertheless stiffen the structure and thus result overall in a stiffening. 
         [0030]    In exemplary embodiment the housing in the region of a neutral fiber can have a wall thickness smaller than the wall thickness in a region adjacent to the neutral fiber. 
         [0031]    A neutral fiber indicates the region of a body that experiences no changes in length in elastostatic stress. Naturally, the tensions there are especially low. It is therefore advantageous to provide the housing regions, lying directly at the neutral fiber of a housing section, with a smaller wall thickness than housing regions farther removed from the particular neutral fiber. Dimensioning of the wall thickness with consideration of the courses of the neutral fibers contributes to a weight reduction of the housing. 
         [0032]    It can also be expedient for the first regions to be bearing structures of the housing, whereby the second regions form the air-guiding structures of the housing. 
         [0033]    The first regions can be the regions that contribute to the structural integrity and stability of the housing. For example, they form the mounting points for valves, heat exchangers, actuators, and other components in the housing interior. In addition, the housing within these regions is connected to the structures surrounding the housing. 
         [0034]    The second regions can be air-guiding or in general fluid-guiding regions. These are, for example, the flow channels in the housing interior. Partition walls can also be included here. These second regions advantageously have a lower strength than the first regions. 
         [0035]    Furthermore, the air-guiding regions and/or the bearing structures can have a sandwich construction, whereby a fabric layer, a honeycomb layer, or a foam layer, and a fabric layer are provided successively. 
         [0036]    Walls and housing sections in a sandwich construction are especially advantageous, because they offer a high strength at a low weight. Use of the sandwich structures therefore can reduce the overall weight of the housing. In this regard, to achieve a stable structure, a honeycomb layer can be advantageously covered by a fabric layer or a film layer. 
         [0037]    The fabric layer can be made of glass fiber and/or plastic fiber and/or aramid fiber and/or carbon fiber. This is advantageous, because the aforementioned structures are distinguished in particular by a low weight with a simultaneously high strength and stability. 
         [0038]    The honeycomb layer can be advantageously made of aramid paper and/or aluminum and/or plastic and/or a foam. 
         [0039]    As an alternative to a honeycomb layer, a foam layer can also be provided. This is advantageous especially in the case of bearing structures. A structural foam such as, for example, polymethacrylimide (PMI) can be used advantageously as the foam. In an alternative embodiment, the foam can also be interspersed in addition with a honeycomb structure. Alternatively, along the force paths of the housing in the foam or adjacent to it, unidirectional bands, for example, made of carbon fiber, glass fiber, or plastic fiber, can be provided which run along the force path and provide additional stabilization. 
         [0040]    It is especially advantageous in this regard for the air-guiding structures to have a lowest possible weight proportion and the bearing structures have the greatest possible strength. 
         [0041]    It also to be preferred, if the air-guiding regions and/or the bearing structures have a sandwich construction, whereby a fabric layer is arranged at least on one side on a honeycomb layer or a foam layer. 
         [0042]    This is particularly advantageous in that a still lighter structure can be produced by an only one-sided arrangement. 
         [0043]    In an alternative embodiment of the invention, it is provided in addition that the bearing structures are formed by aluminum die casting and/or magnesium die casting, whereby the metallic structures are covered at least partially by a fabric and/or overmolded with a thermoplastic and/or surrounded by films. 
         [0044]    Components produced in aluminum die casting or magnesium die casting are distinguished by a high strength at a low weight. For additional reinforcement, these components can be covered or surrounded with fabric and/or films, as has already been described above. Such fabric and/or films can also be inserted in the metallic components and fixed there, for example, by an adhesive. Alternatively, the metallic components can be overmolded with a thermoplastic. 
         [0045]    A supporting framework can be provided, whereby the supporting framework is formed of profile elements. In an alternative embodiment of the invention, it can be provided that the supporting framework is surrounded at least partially by a fabric and/or by a thermoplastic and/or by a film. In so doing, the fabric and/or thermoplastic and/or film can be arranged both on the outwardly facing side of the supporting framework and on the inwardly facing side of the supporting framework. 
         [0046]    A supporting framework can be a frame, produced from a plurality of profile elements, or a skeleton, which can be surrounded by fabric pieces and/or films, in order to form a closed housing. Advantageously, only a section of the housing can be formed by such a supporting framework. 
         [0047]    In an exemplary embodiment, the supporting framework can be formed by hollow profile elements, such as, for example, I, T, or U profiles. In addition to the I, T, or U profiles, tubes with a circular or oval cross section can also be used, for example. In this regard, the supporting framework can be designed such that primarily the walls outwardly limiting the housing are formed by the surrounded supporting framework or also the inner structure of the housing. The supporting framework can be configurerd advantageously of multiple parts as well in order to assure a simpler assembly. 
         [0048]    According to an embodiment of the invention, it can be provided that the first regions of the housing form regions that are acted upon by greater mechanical stresses in comparison with the second regions. 
         [0049]    In this regard, in particular mechanical stresses are meant that during operation act on the housing of the climate control system. 
         [0050]    Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0051]    The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus, are not limitive of the present invention, and wherein: 
           [0052]      FIG. 1  shows a schematic view of the housing of a climate control system with an evaporator, heater, air outlet openings, an air inlet opening, and a valve; 
           [0053]      FIG. 2  shows a perspective view of a supporting framework made of profile elements, whereby a surface of the supporting framework is covered or surrounded by a material; 
           [0054]      FIG. 3  shows a partial view of a housing segment, whereby the housing has first regions and second regions, whereby the first regions have a greater wall thickness than the second regions; and 
           [0055]      FIG. 4  shows a further partial view of a housing segment, whereby the housing is formed with a sandwich-like construction. 
       
    
    
     DETAILED DESCRIPTION 
       [0056]      FIG. 1  shows a schematic view of a climate control system  1 . Climate control system  1  has in its interior, by way of example, an evaporator  2  and a heater  3 , which are disposed in an air flow section  8 . Furthermore, a valve  4 , which can close an air outlet opening  5 , is disposed in the interior of climate control system  1 . To this end, valve  4  is mounted rotatable at housing  9  of the climate control system. 
         [0057]    Housing  9  furthermore has an air inlet opening  10  and two air outlet openings  6 ,  7 . A partition wall  11 , which guides the air flow in the top part of housing  9 , is disposed in the air flow direction downstream of heater  3 . 
         [0058]    The illustrated components in climate control system  1  are only exemplary. More or fewer heat exchangers, valves, air inlet openings, or air outlet openings can also be provided in alternative embodiments. Likewise, the number and arrangement of the partition walls in the interior of climate control system  1  can vary. As a result, further air flow sections and flow paths can be formed in the interior of the housing. 
         [0059]    Housing  9  has first regions  12 ,  13 ,  14 , and  15 , which have a much greater wall thickness than the other regions  16  to  20 . Evaporator  2  is accommodated between first regions  12  and  13 . Furthermore, first region  12  has a mounting point  21 , which is used for connecting housing  9  to structures (not shown here) in the vehicle. 
         [0060]    First region  14  is arranged adjacent to air outlet opening  5  and in the interior has connecting point  22  for valve  4 . Valve  4  is mounted rotatable around said connecting point  22 . A further first region  15  is used for accommodating heater  3 . 
         [0061]    First regions  12  to  15  are included in the bearing structures of housing  9 , forming connecting points for components  2 ,  3 ,  4 , disposed in housing  9 , and/or functioning as outer connecting points  21  for structures surrounding housing  9 . During operation, the mechanical stresses at these regions are greater than, for example, in second regions  16  to  20 , which further form housing  9 . 
         [0062]    First regions  12  to  15  in  FIG. 1  have a convex curvature outward. This design is exemplary. In alternative embodiments, concave courses can also be provided or wall regions running parallel to one another. 
         [0063]    The second regions  16  to  20  are primarily formed with thin walls and take over mainly the air-guiding tasks in climate control system  1  shown in  FIG. 1 . In other words, they form air flow section  8  primarily in the interior of housing  9 . The second regions  16  to  20  therefore advantageously have an especially thin-walled design in order to keep the weight of housing  9  as minimal as possible. Housing  9  is preferably made of multiple parts so that easy assembly is possible. 
         [0064]    Housing  9  is advantageously made of plastic, fabric, a film, or metal. Coated walls can be used which, for example, provide fabric-surrounded honeycomb structures. Alternatively, foams can also be used to produce a stable and the lightest housing  9  possible. 
         [0065]    The elements forming housing  9  can be formed similar to the “tailored blanks” method, already known from metalworking. This means that the wall thickness of housing  9  at each location is tailored to the mechanical stresses actually arising during later operation. This allows for a smooth transition between first regions  12  to  15  with a thicker wall thickness and second regions  16  to  20  with a smaller wall thickness. 
         [0066]    Partition wall  11  that has only an air-guiding function, can be formed from a supporting framework, for example, which is surrounded by a fabric and/or film. An especially light yet stable partition wall  11  can be produced in this way. The supporting framework can include advantageously one or more profile elements are joined together to form a frame or another supporting structure. 
         [0067]    In an alternative embodiment, the first regions can also be produced with an increased material thickness in which a suitable reinforcing component is applied to a thin-walled housing. To this end, for example, fabric structures or films can be glued onto the housing. Alternatively, the housing can be surrounded by a fabric and/or film at appropriate locations. The description for  FIG. 3  contains further embodiments in this regard. 
         [0068]      FIG. 2  shows by way of example a rectangular supporting framework  30 , made of a plurality of profile elements  31 . In this case, profile elements  31  are advantageously glued, screwed, or soldered together or, for example, connected to one another by plug connections. 
         [0069]    Any supporting framework geometries can be produced by suitable dimensioning of profile elements  31  and a suitable positioning to one another. 
         [0070]    Supporting framework  30  in  FIG. 2  is covered, at least on the surface facing the viewer, with a material  32 . Material  32  here can be, for example, a film and/or fabric, as has already been described further above. An at least partially or completely closed supporting framework  30  can be produced in this way, which forms, for example, an air flow section in the interior. In an alternative embodiment, the supporting framework can also be covered or surrounded partially as in  FIG. 2  and covered partially with a wall made of a plastic or a metallic material. 
         [0071]    The structure closing the housing outwardly, as well as sections of the housing, disposed in the interior of the housing, such as, for example, air channels, can be formed over a supporting framework  30 . 
         [0072]      FIG. 3  shows a partial view of a housing  40 , whereby two second regions  45 ,  46  and two first regions  41 ,  43  are shown. The left first region  41  is formed by a reinforcing component  42 , which was applied to thin-walled housing  40 . Reinforcing component  42  is preferably glued to housing  40  or housing  40  is back-injected with reinforcing component  42 . Alternatively, such a first region with a greater wall thickness can also be achieved by the selective influencing of an injection molding tool. 
         [0073]    The right first region  43  is formed by reinforcing component  44 , which is disposed on both sides of housing  40 . Housing  40  is thus surrounded both on the upward facing surface and on the downward facing surface by reinforcing component  44 . 
         [0074]    Reinforcing component  42  and  44 , as already described, could be formed by films, fabric structures, or also by a thermoplastic. 
         [0075]    Housing  40  can be made of a plastic or, for example, be a part produced in aluminum die casting or magnesium die casting. 
         [0076]      FIG. 4  shows a partial view of a housing  50 , which is produced in a sandwich-like construction. In this case, both outer layers  51 ,  52  are each formed by a fabric layer. Middle layer  53  in  FIG. 4  is either formed by a honeycomb structure  54 , as shown on the right, or by a foam layer  55 , as shown on the left. 
         [0077]      FIG. 4  is an exemplary illustration. Advantageously, either a honeycomb-like structure  54  or a foam layer  55  is provided. In an alternative embodiment, however, a mixed structure of honeycomb  54  and foam  55  can also be provided. In further alternative embodiments, a layer  51  or  52  can also be applied only on one side to honeycomb-like structure  54 , foam layer  55 , or the mixed structure. Layer  51 ,  52  can be disposed both on the outwardly facing surface of the housing and on the inwardly facing surface of the housing. 
         [0078]    The features of the exemplary embodiments of  FIGS. 1 to 4  can be combined with one another. The shown  FIGS. 1 to 4  do not suggest any limiting effect. The figures are used to clarify the inventive concept and are not limiting particularly with respect to their geometry, material selection, and dimensioning. 
         [0079]    The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are to be included within the scope of the following claims.