Patent Publication Number: US-2022227410-A1

Title: Steering Column Cover and Steering Column Having a Steering Column Cover

Description:
BACKGROUND AND SUMMARY OF THE INVENTION 
     The invention relates to a steering column cover. It furthermore relates to a steering column having such a steering column cover and to a motor vehicle having such a steering column. 
     The axial adjustability of the steering column of a motor vehicle by means of the steering shaft section emerging from the steering wheel is standard nowadays in order to be able to adapt the position of the steering wheel to the sitting position and the physical dimensions of the driver. The region of the steering column between the steering wheel and the dashboard, from which the steering column with the steering wheel protrudes, is covered with a steering column cover. In passenger vehicles, conventional steering column coverings cover an axial movement path of approximately 60 mm in the longitudinal direction of the steering column. 
     In the case of future, fully autonomous motor vehicles, the steering wheel is not required during the fully autonomous driving mode, and there is an endeavor, in these phases of the driving mode, to place the steering wheel against the dashboard or to position it in a corresponding recess in the dashboard so that the driver obtains greater freedom of movement. For this purpose, however, an axial movement path of the steering column is required which is significantly larger than in the case of currently provided steering column covers and which is, for example, 160 mm or more. The movement path has to be provided by a future steering column cover. In addition, however, the restricted installation space in the region of the dashboard also has to be taken into consideration. 
     GB 490 959 A discloses a motor vehicle steering wheel which is movable axially on a steering shaft, in which a volute spring which is wound around the steering shaft is provided between the steering shaft end of the steering wheel and a collar surrounding the steering shaft, the volute spring surrounding the free end of the steering shaft in the displacement region of the steering wheel and pretensioning the steering wheel into a maximally extended position. 
     EP 3 083 368 B1 discloses a steering column cover for tractors, which consists of a lower and an upper cup-like cover part. The lower cover part is connected to a dashboard-like section of the body and the upper cover part is connected to the steering wheel. The lower edge of the upper cover part overlaps the upper edge of the lower cover part, which edge merges into a radially extending, upper wall of the lower cover part, in which a seal engaging around the steering shaft is provided. During an axial adjustment of the steering wheel, the two cover parts which engage in each other enable a telescopic expansion or compression of the steering wheel cover. The axial length of the respective cover part determines the minimum extent and the maximum extent of the variable part of the steering column cover and therefore the usable movement path of the steering column, in which the steering column cover is effective. 
     It is an object of the present invention to provide a steering column covering which covers the region of the steering column between the steering wheel and the dashboard over a longer movement path even when installation conditions are restricted. 
     This object is achieved with the features of the independent claim. 
     A steering column cover of a steering column having steering column elements which are movable relative to one another in the direction of the steering column axis has a plurality of casing elements which surround the steering column, are arranged one behind another in the axial direction and engage telescopically in one another, wherein, according to the invention, the casing elements are coupled to one another by the gear mechanism. 
     The steering column cover according to the invention is provided with a plurality of, preferably at least three, tubular casing elements which have different outside diameters at least in regions and engage telescopically in one another and can thus be pushed into one another in order to move from a maximum length to a minimum position. The coupling of the casing elements to one another by means of the gear mechanism has the effect that, in the event of an axial compression and also in the event of an axial expansion of the steering column cover, the casing elements move synchronously relative to one another and therefore a defined axial displacement of the individual casing elements with respect to one another always takes place. 
     Further preferred and advantageous refinement features of the steering column cover according to the invention are the subject matter of the dependent claims. 
     A first casing element is preferably coupled to a first steering column element which is movable in the axial direction, for example the steering wheel. The steering column cover together with the axially movable steering column element is thereby moved in both axial directions and is thus inevitably driven by the drive of the movable steering column element. During compression of the steering column in the axial direction, the final casing element which is positioned away from the first casing element is supported on a steering column element which is rigid in the axial direction or on the dashboard or on another part of the vehicle structure, thus enabling the compression, which is synchronized by the gear mechanism, of the telescopic steering column covering to be initiated. It may be of advantage here if at least one further casing element, for example the final casing element, is coupled to a further steering column element, which is rigid in the axial direction, or to the dashboard or to another part of the vehicle structure. It can thereby be ensured that also in the event of an extension of the steering column, the telescopic steering column covering, synchronized by the gear mechanism, expands uniformly and, in the process, always covers the free end of the steering shaft in the movement range of the steering column. 
     In a first advantageous embodiment of the steering column cover according to the invention, the gear mechanism is a scissor mechanism. 
     In a second advantageous embodiment of the steering column cover according to the invention, the gear mechanism has racks and pinions meshing therewith. 
     In a particular preferred embodiment, the first, radially outer casing element has a rack, the row of teeth of which meshes with a pinion which is mounted rotatably on a second casing element, which is arranged radially inward from the first casing element, wherein the axis of rotation of the pinion is placed in a plane which extends at a right angle to the steering column axis, and wherein a third casing element is provided radially inward from the second casing element, the third casing element having a second rack, the row of teeth of which is in meshing engagement with the pinion of the second casing element. This rack and pinion drive which couples the individual casing elements to one another ensures that the individual casing elements of the steering column cover moves synchronously with respect to one another during an axial displacement movement of the steering column and always take up a defined position relative to one another. 
     It is of advantage here if the third casing element is provided with a further, third rack which has a further row of teeth which meshes with a further pinion which is mounted rotatably on a fourth casing element, which is arranged radially inward from the third casing element, of a further, radially inner pair of casing elements, wherein the axis of rotation of the further pinion is also placed in a plane which extends at a right angle to the steering column axis, and if the further, radially inner pair of casing elements has, radially inward from the fourth casing element, a fifth casing element which has a fourth rack, the row of teeth of which is in meshing engagement with the further pinion of the fourth casing element. This development of the steering column cover comprises two further casing elements which are likewise incorporated into the gear mechanism coupling of the casing elements which are already present, and which extend the possible displacement path of the steering column cover, and therefore of the steering column, for maintaining the advantages already described. 
     It is furthermore advantageous if radially within the further, radially inner pair of casing elements at least one further pair of casing elements is also provided which is configured analogously to the above-described configuration. By adding such further pairs of casing elements, which are coupled to one another by the rack and pinion drive arrangement, the displacement part of the steering column cover, and therefore the steering column, can be further increased while retaining the advantages mentioned. 
     Preferably, the length and/or the pitch of all the racks and the diameter and/or the pitch of all the pinions are identical, thus enabling a symmetrical relative displacement of all the casing elements with respect to one another to be achieved. 
     The invention is also directed toward a steering column having a steering column cover configured according to the invention. It is furthermore directed toward a motor vehicle having such a steering column. 
     Preferred exemplary embodiments of the invention with additional refinement details and further advantages are described and explained in more detail below with reference to the attached drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows an axially adjustable steering column with a first embodiment of a steering column covering according to the invention; and 
         FIG. 2  shows an axially adjustable steering column with a second, alternative embodiment of the steering column covering according to the invention. 
     
    
    
     DETAILED DESCRIPTION OF THE DRAWINGS 
       FIG. 1  shows the steering column  1  of a motor vehicle  2  in a partially sectioned illustration with a steering column cover  3 . The steering column  1  has a steering wheel  10  and a tubular first steering column element  12 , which is connected nonrotatably to the latter, and a second steering column element  14  which is formed by a part of a steering shaft  13  protruding from a dashboard  20  of the vehicle. The steering shaft is connected in a conventional manner to a steering gear of the vehicle steering system. 
     The two steering column elements  12 ,  14  are coupled to one another nonrotatably, but so as to be displaceable along the steering column axis A, wherein a locking mechanism, not illustrated in the drawing, is provided with which the two axially movable steering column elements  12 ,  14  can be fixed relative to one another in the axial direction. Such locking mechanisms for axially adjustable steering columns are conventionally known and configured, for example, as clamping mechanisms. The steering column element  30  which is connected to the steering wheel  10  can be displaced axially manually or by means of a motorized adjustment drive. 
     The two steering column elements  12 ,  14  are surrounded in their displacement range by the steering column cover  3  which extends between the steering wheel  10  and the dashboard  20 . The steering column cover  3  consists of a plurality of casing elements  30 ,  32 ,  34 ,  36 ,  38  which surround the steering column  1  and are arranged one behind another in the axial direction and are substantially tubular, have diameters different from one another and engage telescopically in one another, as can be seen in  FIG. 1 . The casing elements  30 ,  32 ,  34 ,  36 ,  38  are arranged nonrotatably relative to one another and also nonrotatably relative to the steering wheel  10  or relative to the dashboard  20  such that the steering column cover  3  which is formed by them either rotates together with the steering wheel, or the steering wheel  10  is rotatable relative to the steering column cover  3 . 
     The radially outer, first casing element  30  is coupled, at least in the axial direction, to that end section  11  of the steering wheel  10  which faces the dashboard, that is to say that axial displacement movements of the steering wheel  10  along the steering wheel axis A are transmitted from the steering wheel  10  to the first casing element  30 . The final, radially innermost casing element  38  is coupled in an axially fixed manner to the dashboard  20 . In the example shown in  FIG. 1 , five casing elements are provided, but the invention is not restricted to this number of casing elements. It is possible also to provide more or fewer casing elements, with them preferably forming an uneven number. 
     The casing elements  30 ,  32 ,  34 ,  36 ,  38  are coupled to one another by a gear mechanism  4 . In the example shown in  FIG. 1 , the gear mechanism  4  is configured as a rack and pinion drive and has racks  40 ,  42 ,  44 ,  46  and pinions  41 ,  45 . 
     On the radially inner side of its wall  31  in the region of its front end  30 ′ facing the dashboard  20 , the first, radially outer casing element  30  on the steering wheel side has a first rack  40  which runs parallel to the steering wheel axis A and the row of teeth  40 ′ of which meshes with a pinion  41  which is mounted rotatably in or on the wall  33  of the second casing element  32 , which is arranged radially inward from the first casing element  30 . The axis of rotation  41 ′ of this first pinion  41  lies in a first plane E 1  which extends at a right angle to the steering column axis A. 
     The third casing element  34  is provided radially inward from the second casing element  32 , the third casing element being provided, at its rear end section  34 ″ facing the steering wheel  10  on the radially outer side of its wall  35 , with a second rack  42  of the gear mechanism  4 , the row of teeth  42 ′ of which rack faces radially outward and likewise runs parallel to the steering column axis A. The second rack  42  is positioned in the same plane E in which the first rack  40  lies and in which the first pinion  41  extends; this plane E corresponds to the plane of the drawing in  FIG. 1 . The second rack  42  is likewise in meshing engagement with the first pinion  41  of the second casing element  32 . 
     On the radially inner side of the wall  35  of the third casing element  34 , in the front end section  34 ′ facing the dashboard  20 , a further, third rack  44  is provided, the (further) row of teeth  44 ′ of which extends parallel to the steering column axis A and preferably likewise in the plane E. The third rack  44  for its part is again in meshing engagement with a second pinion  45  of the gear mechanism  4 . The second pinion  45  is mounted rotatably in or on the wall  37  of the fourth casing element  36  arranged radially inward from the third casing element  34 . The axis of rotation  45 ′ of the second pinion  45  lies in a second plane E 2  which likewise extends at a right angle to the steering column axis A and therefore parallel to the first plane E 1 . 
     Radially inward from the fourth casing element  36 , the fifth casing element  38  (the final one in the example of  FIG. 1 ) is provided which, on the radially outer side of its wall  39  on the rear end section  38 ″ thereof facing the steering wheel, is provided with a fourth rack  46  of the gear mechanism  4 , the row of teeth  46 ′ of which faces radially outward and likewise runs parallel to the steering column axis A. The fourth rack  46  is positioned in the same plane E in which the other racks  40 ,  42 ,  44  are also located and in which the pinions  41  and  45  of the gear mechanism  4  extend. The front end section  38 ′ of the fifth casing element  38  that faces away from the steering wheel  10  is coupled fixedly in the axial direction to the dashboard  20 , as has already been explained. 
     In the region in which the steering column  1  emerges from the dashboard  20 , the dashboard  20  has a trough-like depression  22  in which the steering column  1  can be accommodated in the pushed-together state (in the direction of the arrow A′ in  FIG. 1 ). In the pushed-together state, the steering wheel  10  lies directly against the dashboard  20  or is itself recessed in a corresponding recess of the dashboard such that the steering wheel  10  does not protrude into the passenger compartment during a fully autonomous driving mode.  FIG. 1  shows the extended state of the steering column  1 . 
     An axial movement of the steering wheel  10  in the direction of the arrow A′ has the effect that the individual casing elements  30 ,  32 ,  34 ,  36 ,  38  of the steering column cover  3  are pushed telescopically into one another, wherein the intermeshing racks and pinions of the gear mechanism  4  synchronize this telescopic movement such that a uniform distance of the individual casing elements  30 ,  32 ,  34 ,  36 ,  38  with respect to one another in the axial direction is always obtained irrespective of the axial position of the steering wheel  10 . In a corresponding manner, the racks and pinions of the gear mechanism  4  synchronize the telescopic movement of the casing elements  30 ,  32 ,  34 ,  36 ,  38  also when the steering wheel  10  is being pulled out of the dashboard  20  counter to the direction of the arrow A′. 
       FIG. 2  shows an alternative embodiment of the steering column cover  103 , in which the gear mechanism  104  is formed by a scissor mechanism; otherwise, this alternative embodiment of the steering column cover is constructed in the same manner as the embodiment from  FIG. 1 , but wherein here preferably an even number of casing elements is provided, as is also illustrated in  FIG. 2 . According thereto, the dashboard-side fourth casing element  136  is coupled in the axial direction to the dashboard  120 . The first casing element  130  which faces away from the dashboard  120  is coupled in the axial direction to the steering wheel  110  or to a first steering column element  112  on the steering wheel side. The respective central joint connectors  140 ,  140 ′,  140 ″,  140 ′ of the individual scissor elements  141 ,  141 ′,  142 ,  142 ′,  143 ,  143 ′,  144 ,  144 ′ are connected to a respective casing element  130 ,  132 ,  134 ,  136  and the respective outer joint connectors  145 ,  145 ′,  146 ,  146 ′,  147 ,  147 ′ are decoupled from the casing elements  130 ,  132 ,  134 ,  136 . The scissor mechanism synchronizes the relative movements of the casing elements  130 ,  132 ,  134 ,  136  with respect to one another such that it is also ensured in this embodiment that the casing elements  130 ,  132 ,  134 ,  136  can move telescopically in synchronism. 
     The invention is not restricted to the above exemplary embodiment which serves merely to provide a general explanation of the core concept of the invention. Rather, within the scope of protection, the apparatus according to the invention can also take on configurations other than those described above. In particular, the apparatus here can have features which constitute a combination of the respective individual features of the claims. 
     Reference signs in the claims, the description and the drawings serve merely to provide a better understanding of the invention and are not intended to limit the scope of protection. 
     LIST OF REFERENCE SIGNS 
     
         
           1  Steering column 
           2  Motor vehicle 
           3  Steering column cover 
           4  Gear mechanism 
           5  Scissor mechanism 
           10  Steering wheel 
           11  End section of the steering wheel 
           12  Steering column element 
           13  Steering shaft 
           14  Steering column element 
           20  Dashboard 
           22  Trough-like depression 
           30  Casing element 
           30 ′ Front end of  30   
           31  Wall of  30   
           32  Casing element 
           33  Wall of  32   
           34  Casing element 
           34 ′ Front end section of  34   
           34 ″ Rear end section of  34   
           35  Wall of  34   
           36  Casing element 
           37  Wall of  36   
           38  Casing element 
           38 ′ Front end section of  38   
           38 ″ Rear end section of  38   
           39  Wall of  38   
           40  Rack 
           40 ′ Row of teeth 
           41  Pinion 
           41 ′ Axis of rotation 
           42  Rack 
           42 ′ Row of teeth 
           44  Rack 
           44 ′ Row of teeth 
           45  Pinion 
           45 ′ Axis of rotation 
           46  Rack 
           46 ′ Row of teeth 
           103  Steering column cover 
           104  Gear mechanism 
           110  Steering wheel 
           112  Steering column element 
           120  Dashboard 
           130  First casing element 
           132  Second casing element 
           134  Third casing element 
           136  Fourth casing element 
           140  Joint connector 
           140 ′ Joint connector 
           140 ″ Joint connector 
           140 ′″ Joint connector 
           141  Scissor element 
           141 ′ Scissor element 
           142  Scissor element 
           142 ′ Scissor element 
           143  Scissor element 
           143 ′ Scissor element 
           144  Scissor element 
           144 ′ Scissor element 
           145  Outer joint connector 
           145 ′ Outer joint connector 
           146  Outer joint connector 
           146 ′ Outer joint connector 
           147  Outer joint connector 
           147 ′ Outer joint connector 
         A Steering column axis 
         A′ Arrow 
         E Plane 
         E 1  First plane 
         E 2  Second plane