Patent Document

BACKGROUND OF THE INVENTION 
     The present invention relates generally to a spindle bearing for essentially parallel spindles and more specifically to spindle bearings for essentially parallel spindles of air flaps in a vehicle heating, ventilating and/or air conditioning unit. 
     DESCRIPTION OF THE PRIOR ART 
     In the case of many applications, for example in a two- or multi-zone air conditioning system, corresponding ducts for particular zones are formed in an air-conducting housing, said ducts being separated from one another by means of dividing walls. In order to make it possible to adjust the air throughput, the mixture ratio of fresh air to warm air or other aerothermic parameters, an air flap is conventionally provided in each duct formed in this manner, said air flap being articulated in its end regions on a wall or intermediate wall of the air-conducting housing. 
     A known spindle bearing of this type, as is currently being used in-house by the applicant, is illustrated in FIG.  1 . As can be seen, bearing devices  40 ,  50  which can be used as bushes for particular spindles  20 ,  30  are provided on both sides of a dividing wall  10  of an air-conducting housing (not illustrated). Particularly in the case where, as illustrated, the spindles are virtually aligned with each other, there is the problem that the engagement between the bearing device  50  and spindle  30 , on the one hand, and bearing device  40  and spindle  20 , on the other hand, is either very small or the projection of the bearing device requires too much structural space, which has the consequence that either the air flap mounted on the spindles has a complex shape or else that the clear cross section is reduced. 
     SUMMARY OF THE INVENTION 
     The object of the present invention is therefore to develop a known spindle bearing for essentially parallel spindles, in particular of air flaps in a vehicle heating, ventilating and/or air conditioning unit, having respective bearing bushes in such a manner that an improved bearing arrangement and/or a more compact configuration is made possible. 
     According to the invention, this object is achieved by a spindle bearing having the features of claim  1 . Preferred embodiments are defined in the dependent claims. 
     In particular, the invention proposes a spindle bearing for essentially parallel spindles, in particular of air flaps in a vehicle heating, ventilating and/or air conditioning unit, having respective bearing bushes, in which the bearing bushes at least partially overlap in the axial direction. In other words, the space formed by one bearing bush can be used to accommodate the other bearing bush, in order thus to increase the supporting surface for a mounted spindle and/or in order to reduce the required structural space, in particular the size of a dividing wall, in the region of the spindle bearing. It should be understood that the at least partial overlap of the bearing bushes does not absolutely have to correspond to a corresponding overlap of the respective engagement with spindle sections. On the contrary, it would also be conceivable for the bearing engagement of the left spindle to occur further to the right than the corresponding engagement of the right spindle. It should also be understood that in order to support the bearing arrangement, means may additionally be provided, which means essentially fulfill the function of a known bearing arrangement. 
     The solution according to the invention also has the advantage that the installation process is improved, specifically irrespective of whether installation is begun with the one or other spindle, since the spindles can in each case enter deep into the dividing wall. The risk, which usually exists on account of the spindles being inclined, of installation being undertaken wrongly is therefore considerably reduced. 
     The bearing bushes are advantageously designed essentially coaxially with one another. It is therefore possible, for example, to mount a first air flap by means of its spindle in the dividing wall while a further flap is mounted in the first flap, in particular in the spindle end section. 
     The end sections of the spindles may be of integral design or else have corresponding engagement devices, it being preferred in each case for it to be possible for the spindles to be essentially aligned with each other after installation. 
     As an alternative to a coaxial design, the solution according to the invention can likewise be used in order to mount two spindles eccentrically and essentially parallel to each other. This would have the result that instead of the otherwise independent activation of the two air flaps, there is a certain interaction. 
     In the case of one preferred embodiment, one of the bearing bushes is formed in the bearing engagement section of the other spindle/air flap. 
     A part forming a bearing bush is advantageously at the same time a bearing journal. It should be mentioned in this connection that the bearing arrangement can also be undertaken by means of a number of bearing bushes for one and the same spindle. For example, it would be possible to mount a spindle both with regard to the dividing wall and also within the end section of the other spindle. 
     In order to permit a defined installation process and/or a retaining of the position after the installation of the individual air flaps and/or the associated spindles, a device restricting the axial movement is advantageously provided on at least one spindle, in particular on each spindle. 
     It is also preferred for at least one sealing device to be provided, which sealing device can, on the one hand, prevent the ingress of contaminants into the bearing region and, on the other hand, can prevent air from passing through the dividing wall. In the case of a particularly preferred embodiment, each spindle end has a sealing device injection-moulded onto it. In addition to the sealing function, a sealing device can also assist in restricting the axial movement or can take it on by itself, it also being possible for there to be a snap-in function in order to indicate, for example to the person undertaking the installation, that the respective spindles have been correctly installed. 
     In order to simplify the introduction of one spindle end into the corresponding bearing bush, a bevel is advantageously formed on at least one spindle end or bearing part. 
     Finally, it is preferred for the bearing bushes to overlap by at least the thickness of an intermediate wall, in particular by at least 4 mm. 
    
    
     DESCRIPTION OF THE DRAWINGS 
     Further advantages and features of the present invention also result from the following description, which is given merely by way of example, of currently preferred embodiments, said description being undertaken with reference to the attached drawings in which: 
     FIG. 1 shows a spindle bearing arrangement according to the prior art. 
     FIG. 2 shows a first preferred embodiment of a Spindle bearing as claimed in the invention. 
     FIG. 3 shows a further preferred embodiment of a Spindle bearing as claimed in the invention. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     As is illustrated in FIG. 1, two spindles  20 ,  30  have frequently to be articulated with respect to an intermediate wall  10 , this having been hitherto achieved by the formation of bearing bushes on both sides. 
     The embodiment shown in FIG. 2 is likewise concerned with mounting spindles  20 ,  30  together with associated air flaps (not illustrated) with respect to an intermediate wall  10 , the intention being to reduce the structural space requirements and/or to increase the supporting surfaces. The intermediate wall  10  defines a bearing surface  12 , in which an end section of the spindle  30  can engage. For this purpose, a separate bearing bush  50  or else the air flap itself can form a hollow bearing journal, which is in engagement with the bearing surface  12  via a bearing bush surface  52  of the bearing bush  50 . Opposite the bearing bush surface  52 , the bearing bush  50  forms a cavity, which defines a bearing bush surface  54 . The two bearing surfaces  12  and  54  therefore overlap by at least a thickness of the intermediate wall  10 . 
     Situated within the bearing bush surface  54  is a bearing bush  40  of the other spindle  20 , which can be of integral design with the spindle  20 , can be present as a separate part or else can be part of the air flap itself. As illustrated in FIG. 2, the bearing bushes  40  and  50  directly engage each other and at least partially overlap in the axial direction. A bearing bush surface  42  of the bearing bush  40  therefore forms a bearing journal which can interact with the bearing bush surface  54 . 
     In order to limit the axial movements of the spindles  20  and  30 , respective bearing surfaces  46 ,  56  are provided on the bearing bushes  40  and  50  respectively, which can interact with side surfaces of the bearing surface  12  of the intermediate wall  10 . As illustrated, the respectively distal ends of the spindles or of engagement sections of the bearing bushes  40  and  50  are of beveled design in order to simplify the respective insertion. 
     FIG. 3 illustrates a further preferred embodiment of a spindle bearing arrangement according to the invention. In the same manner of the embodiment illustrated in FIG. 2, this embodiment concerns mounting two spindles  20 ,  30  with respect to an intermediate wall  10 . In the case of the embodiment shown in FIG. 3, the bearing arrangement is substantially improved by the fact that a relatively thick overlap region is provided between the bearing bushes. 
     The intermediate wall  10  in turn forms a bearing bush surface  12 , with which a part of the right spindle  30  can interact, via an engagement surface  52   a . In the embodiment illustrated, sealing devices  13 ,  14  are likewise illustrated on both sides of the intermediate wall  10 , which sealing devices ensure, on the one hand, that no contaminants can enter the bearing region and, on the other hand, ensure that no leakage of air is possible. In the embodiment illustrated, the sealing devices  13 ,  14  are firmly connected to the spindle ends, for example by means of injection molding, with the result that the distal end sections of the sealing devices  13 ,  14  bear against the intermediate wall and can therefore restrict the axial movement of the spindles. As an alternative, it would also be possible to fasten the sealing devices  13 ,  14  to the intermediate wall  10 , instead of to the respective spindles, which would enable a corresponding snap-in function to take place. In this case, the engagement of the sealing device  14  with the surface  42   b  could align and support the left spindle  20  and the engagement of the sealing device  13  with the surface  52   b  could align and support the right spindle  30 , specifically also without the correspondingly other bearing device being present in each case. 
     A cavity which defines a bearing bush surface  54  within it is formed in the right spindle  30 . The end section of the other spindle  20  can be inserted into this bearing bush, the surface section  42   a  acting in the manner of a bearing journal. The spindle  20  is therefore mounted within the spindle  30 , a respective bearing surface  56  and  46  being formed both for the spindle  30  and the spindle  20 , in order to be able to restrict the axial movement. 
     In addition to the clear overlap, the embodiment shown in FIG. 3 is distinguished in that the installation sequence is as desired, since both bearing ends enter to a substantial extent through the wall  10 , air being effectively prevented from passing through, by means of the sealing devices. 
     Although the present invention has been described above entirely with reference to currently preferred embodiments, it should be understood by the expert that a very wide variety of modifications are possible within the framework of the claims. In particular, individual features of one embodiment may be combined as desired with features of another embodiment.

Technology Category: 2