Abstract:
The invention relates to an air diffusor, in particular for vehicle air-conditioning, the air diffusor comprising a housing, a plurality of vanes of which each is pivotally mounted, and an adjustment element by means of which an orientation of the vanes can be adjusted. A first coupling element is provided with which each vane is coupled so as to be rotatable about a first swiveling axle. The first coupling element is supported on the housing so as to slide in a sliding guide, and a second swiveling axle is provided on each vane.

Description:
TECHNICAL FIELD 
     The invention relates to an air diffusor, in particular for vehicle air-conditioning. 
     BACKGROUND OF THE INVENTION 
     Typically, an air diffusor has vanes which can be arranged either horizontally or vertically, and with which the direction of the airflow coming out of the vent can be adjusted. Normally, the vanes can be rotated about axes that are permanently stationary with respect to the housing. In order not to hinder the rotation of the vanes, there has to be sufficient space between the outer vanes and the housing. Consequently, at certain angle positions of the vanes in the edge area, the airflow can only be directed inadequately. Moreover, at certain angle positions, the impression is given of an uneven distribution of the diffusor surface. 
     BRIEF SUMMARY OF THE INVENTION 
     Therefore, the object of the invention is to reduce as much as possible the distance between the external vanes and the housing, especially in the two extreme positions of the vanes, so that there is no undirected airflow in the edge area of the vent. Moreover, at each angle position, a uniform distribution of the vanes across the surface of the diffusor should be possible. 
     This is achieved in an air diffusor which comprises a housing, a plurality of vanes of which each is pivotally mounted, and an adjustment element by means of which an orientation of the vanes can be adjusted. A first coupling element is provided with which each vane is coupled so as to be rotatable about a first swiveling axle. The first coupling element is supported on the housing so as to slide in a sliding guide, and a second swiveling axle is provided on each vane. Due to the fact that the vanes are not swiveled about a single swiveling axle that is permanently stationary with respect to the housing but rather about two swiveling axes, it is possible to maintain a very small distance between the external vanes and the housing by shifting the rotational axes of the vanes, even if the vanes are in their extreme positions. It is aimed for that the topmost and lowermost vanes lie directly against the housing when they are in their respective extreme positions. 
     According to a preferred embodiment of the invention it is provided for that a second coupling element is used that is movable relative to the housing, each of the vanes being coupled to the second coupling element in such a way that it can rotate about the second swiveling axle, and that the adjustment element is connected to the first and second coupling elements in such a way that, by activating the adjustment element, a position of the coupling elements relative to each other and thus an orientation of the vanes can be adjusted. With this embodiment, the shifting of the vanes results from the superposition of two translation movements by the coupling elements. In addition to the advantages listed above, by means of the manner of adjustment of the coupling elements, the arrangement of the vanes in different, tilted positions can be brought about in such a way that the impression is given of an even distribution of the vanes. 
     According to another preferred embodiment of the invention, it is provided for that the second swiveling axle is supported in a sliding guide in the housing, the sliding guide of the second swiveling axle being aligned approximately perpendicular to the sliding guide of the first coupling element. With this embodiment, a simple structure yields essentially the same advantages as with the first embodiment. 
     Advantageous embodiments of the invention will be apparent from the subordinate claims. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a front view of an air diffusor according to a first embodiment in a cut-away view; 
     FIG. 2 is a side view of the air diffusor of FIG. 1; 
     FIG. 3 is an air diffusor according to a second embodiment in a schematic side view; 
     FIG. 4 is a section along the line IV—IV of FIG. 3; and 
     FIG. 5 is an air diffusor according to a third embodiment in a schematic side view. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     FIG. 1 shows an air diffusor  10  according to a first embodiment that has a housing  12  as well as a plurality of vanes  14  arranged therein (also see FIG.  2 ). 
     In the housing, a first coupling element  16  is provided as well as a second coupling element  18 , which are both designed as coupling rods. The first coupling element  16  is supported in the housing  12  in a sliding guide  20 , which is only shown here schematically. A guide for the second coupling element  18  is not necessary. The front end of each of the vanes  14  is supported rotatably on the first coupling element  16  and the rear end of each of the vanes  14  is supported rotatably on the second coupling element  18 . For this purpose, there are provided pegs  22  that engage in corresponding openings in the coupling elements. 
     An adjustment element  24  is rotatably supported in the housing  12  and it is configured as an adjustment wheel here. The adjustment element  24  is provided with a first slot  26  and a second slot  28 . The two coupling elements  16 ,  18  are provided with pins  30  that engage in the slots  26  and  28  respectively, so that the position of the first coupling element  16  is determined by the first slot  26  while the position of the second coupling element  18  is determined by the second slot  28 . 
     By rotating the adjustment element  26 , the orientation of the vanes  14  can be adjusted relative to the housing, so that the direction of an airflow emerging from the diffusor  10  can be adjusted. When the adjustment element  24  is rotated clockwise away from the position shown in FIG. 2 in which the vanes  14  are positioned horizontally, the second coupling element  18  is shifted by the slot  28  downwards relative to FIG. 2, whereas the first coupling element  16  is not moved. This is due to the fact that the pin  30  of the first coupling element enters an area of the slot  26  that is approximately concentric to the rotational axis of the adjustment element  24 . As a result of the shifting of the two coupling elements relative to each other, the rear area of the vanes  14  is moved downwards, whereas the front area remains approximately stationary. Consequently, an airflow coming out of the diffusor is deflected upwards. 
     Depending on the design of the slots, the front coupling element could also be shifted in response to a clockwise rotation so that the shifting of the vanes results from a superposition of two movements. 
     However, when the adjustment element  24  is rotated counterclockwise from the position shown in FIG. 2, the first coupling element  16  is shifted downwards. The second coupling element  18  moves only slightly since the pin  30  of the second coupling element enters an area of the slot  28  that extends approximately concentric to the rotational axis of the adjustment element  24 , that is to say, to the left towards the first coupling element relative to FIG. 2, while it remains at about the same height. Thus, the front edge of the vanes  14  is moved downwards and an airflow coming out of the diffusor is deflected downwards. 
     Since the vanes  14  are no longer swiveled about a stationary axis as is the case with a conventional air diffusor, but rather are shifted by means of the superposition of two translation movements by the coupling elements, the two outer vanes can be positioned much closer to the housing  12  and, in the extreme positions, can lie directly against said housing, so that the airflow coming out of the diffusor is deflected in this area as well. 
     In this embodiment, the coupling elements can be shifted by means of the adjustment wheel in such a way that the vanes can be brought into a position that is pivoted by 90° relative to FIG. 2, that is to say, into a vertical position in which they all lie in one plane. In this case, a narrow gap remains between each of the edges of the individual vanes and the air can emerge from the diffusor without being directed in a specific direction. 
     FIGS. 3 and 4 show a diffusor  10  according to a second embodiment. The same reference numerals are used for the components known from the first embodiment, and reference is made to the explanations above. 
     In the second embodiment as well, a first coupling element  16  is provided for sliding movement on the housing and to which the vanes are attached by means of the first swiveling axle  21 . In contrast to the first embodiment, however, there is no second coupling element provided; each vane is supported in the housing by means of the second swiveling axle  22  directly in a second sliding guide  40  (here shown for only one of the vanes). The second swiveling axle  22  is positioned somewhat behind the middle of the vane as seen from the first swiveling axle arranged on the front edge of each vane. 
     The vanes can be swiveled by means of the adjustment element  24  into the desired position, the adjustment element being designed here as an adjustment knob that is mounted directly on one of the vanes so that it is accessible from the outside. 
     With this embodiment, too, the vanes are shifted by means of the superposition of two translation movements; the first swiveling axle  21  is adjusted in the direction established by the first sliding guide  20 , whereas the second swiveling axle  22  is shifted in the direction perpendicular thereto, established by the second sliding guide  40 . 
     FIG. 5 shows an air diffusor according to a third embodiment. Here, like in the first embodiment, a second coupling element  18  is provided on which the vanes  14  are rotatably supported with their second swiveling axle  22 . In order to guide the coupling element, a second sliding guide  40  is provided that is positioned perpendicular to the sliding guide  20  for the first coupling element. Since the parallel arrangement of the two coupling elements is ensured by the connection to the vanes, it is sufficient to have one single sliding guide on the second coupling element. 
     As an alternative, it would also be possible to use an adjustment wheel with a guide for the first coupling element in order to guide the first coupling element, as is fundamentally known from the first embodiment. Then it is possible to dispense with the adjustment knob for purposes of adjusting the vanes.