Abstract:
An apparatus for adjusting the camber and/or toe of a motor vehicle wheel includes a wheel carrier, on which the wheel is rotatably mounted. The wheel carrier is divided into a carrier member receiving the wheel via a wheel bearing, an axle-side guide member, and a bearing assembly arranged therebetween. The bearing assembly includes rotary parts which can be rotated relative to each other and relative to both the carrier member and the guide member and which interact with confronting inclined faces. The wheel bearing includes a radially outer bearing housing, which is clamped by the bearing assembly formed from the rotary parts into a plug-and-socket connection with the carrier member.

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS 
     This application is the U.S. National Stage of International Application No. PCT/EP2010/007477, filed Dec. 9, 2010, which designated the United States and has been published as International Publication No. WO 2011/082756 and which claims the priority of German Patent Application, Serial No. 10 2009 058 489.7, filed Dec. 16, 2009, pursuant to 35 U.S.C. 119(a)-(d). 
     BACKGROUND OF THE INVENTION 
     The invention relates to a device for adjusting camber and/or toe of the wheels of wheel suspensions, in particular for motor vehicles. 
     DE 10 2008 011 367 A1 describes a generic device, wherein the camber and/or toe of the wheels is adjustable while driving by way rotary parts integrated in the wheel carrier. The wheel carrier is hereby divided into a carrier member receiving the wheel and a guide member articulated on wheel suspension elements, which pivot the carrier member relative to the guide member by rotating one or both rotary parts with electric motors and with adjusting drives formed by spur gears. The adjustment is hereby attained in that the rotationally symmetrical rotary parts have a common rotation axis and surfaces or rotary bearings inclined relative to the rotation axis, which when the rotary parts are rotated in the same direction or in opposite directions enable a corresponding pivoting motion of the carrier member by camber and/or toe angles of up to 5°. 
     It is an object of the invention to improve the device of the generic type in order to achieve a robust and easily producible construction of the pivot bearings of the rotary parts including the wheel bearings arranged in the wheel carrier, which also simplifies the assembly of the respective components. 
     SUMMARY OF THE INVENTION 
     According to one aspect of the invention an apparatus for adjusting camber and/or toe of a vehicle wheel includes a wheel carrier supporting the wheel for rotation, wherein the wheel carrier comprises a carrier member having a wheel bearing receiving the wheel. The wheel bearing in which the vehicle wheel is rotatably mounted, has a radially outer bearing housing. The bearing housing is pressed by the bearing assembly formed by the rotary parts into a plug connection with the carrier member. In this way, the wheel bearing can be affixed on the carrier member in a technically simple manner, without requiring additional screw connections for securing the wheel bearing. 
     Preferably, the rotary parts are rotatably mounted on the carrier member and the guide member by way of tapered roller bearings. The bearing housing of the wheel bearing together with the tapered roller bearings may form a bearing assembly that can be assembled and preloaded from o common side. As mentioned above, the aforedescribed actions result in an easy-to-assemble integration of the rotary bearings of the rotary parts with the wheel bearing housing, eliminating screw connections between the bearing housing and the carrier member. The plug connection can have, for example, a telescopic construction, with an axial stop toward the carrier member. 
     It is furthermore proposed that the tapered roller bearings of the rotary parts with a common rotational axis are inclined with respect to each other in an X-shaped bearing arrangement. One inner bearing race of the bearing arrangement is hereby disposed on the bearing housing of the wheel bearing, whereas the other inner bearing race of the bearing arrangement is disposed on an adjusting ring inserted into the guide member. The adjusting ring can be directly or indirectly axially adjustable via a threaded connection in the guide member. This provides an easily adjustable arrangement of the tapered roller bearings in the created bearing assembly without play, with a simultaneous axial preload of wheel bearing housing. 
     The bearing housing of the wheel bearing and/or the adjusting ring adjustment may be efficiently manufactured from bearing steel and may directly incorporate the inner bearing races of the tapered roller bearings. Furthermore, the outer bearing races of the wheel bearing may also be directly incorporated in the wheel bearing housing. 
     In addition, the adjusting ring may preferably be displaceably guided in a hub section of the guide member and may be closed in the axial direction with a threaded ring. This configuration reliably supports and decouples the radial forces and moments on the tapered roller bearings and the axial preload forces. 
     In a particularly advantageous embodiment of the invention, the plug connection of the bearing housing with the carrier member may be composed of an inner cone of the carrier member which widens towards the tapered roller bearings and a corresponding outer cone on the bearing housing. Assembly is simplified because The bearing housing is not only received in the carrier member without any play, but assembly is also simplified because the bearing housing is automatically centered in the carrier member. In particular, the inner cone may be formed with a large support base in a hub section of the carrier member. 
     Furthermore, the rotation axis which is inclined with respect to the common rotation axis of the rotary parts may be defined by an additional tapered roller bearing disposed between the two rotary parts, with the inner bearing race and/or the outer bearing race of the additional tapered roller bearing implemented directly on the rotary parts. 
     According to a modified embodiment of the invention, when the wheel of the wheel suspension having one driven axle is driven via a central cardan shaft, then the joint housing of the cardan shaft may be fixedly connected via a plug connection and a central screw with a hub section of a wheel-bearing wheel flange, with the hub section further including two split inner rings of the wheel bearing and a clamping sleeve. 
     Lastly, a low-weight structure may be produced by making the components receiving the bearing members from steel and the other, less stressed components, such as in particular the guide member and the carrier member of the wheel carrier, from a light metal. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWING 
       An exemplary embodiment of the invention will now be described in more detail. The schematic drawing shows in: 
         FIG. 1  a schematic diagram of the apparatus for adjusting toe and camber angle of a wheel suspension for motor vehicles with a multi-part wheel carrier; 
         FIG. 2  the device of  FIG. 1 , showing the cardanic connection between the guide member and the carrier member of the wheel carrier; 
         FIG. 3  a structural embodiment of the apparatus of  FIGS. 1 and 2 , with a carrier member carrying a wheel, with a guide member articulated on wheel guiding elements of the wheel suspension, and with two rotary parts which can be rotated via two tapered roller bearings and which are combined with the coaxial wheel bearing into a bearing assembly; and 
         FIG. 4  an enlarged partial view of the apparatus of  FIG. 3 , showing only the bearing assembly. 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     For an explanation of the principle of the invention,  FIG. 1  shows in form of a schematic block diagram a wheel guide element or wheel carrier  10  of a wheel suspension for motor vehicles, which is subdivided in the region of the wheel bearings for adjustment of the camber and/or toe of the wheel as follows: 
     The wheel carrier  10  includes a carrier member  12 , in which the wheel and the brake member (brake disk or brake drum) of a service brake of the motor vehicle is rotatably supported. It should be noted that, unless otherwise mentioned, the functional parts of the suspension are of conventional design. 
     Furthermore, the wheel carrier  10  includes a guide member  14  which cooperates with the wheel suspension or optionally forms a part of the wheel suspension. 
     Two substantially rotationally symmetrical rotary parts  16 ,  18 , which are each rotatably connected via respective rotation axes  20 ,  22  with the carrier member  12  and the guide member  14 , are arranged between the carrier member  12  and the guide member  14  as actuating elements. The two rotation axes  20 ,  22  in  FIGS. 1 and 2  are coaxially aligned and extend preferably in the wheel rotation axis. 
     Whereas the contact surfaces  16   a ,  18   a  of the rotary parts  16 ,  18  directly adjacent to the cannier member  12  and the guide member  14  are constructed with rotational symmetry, the rotary parts  16 ,  18  abut each other by way of planar or alternatively according to  FIGS. 3 and 4  by way of conically inclined surfaces  16   b ,  18   b  and are rotatably connected to each other via a rotation axis  24 . According to  FIGS. 1 and 2 , the rotation axis  24  is hereby perpendicular to the inclined surfaces  16   b ,  18   b  and inclined at a defined angle γ with respect to the rotation axis  20  of the rotary part  18 . 
     A respective electric servomotor  26 ,  28  is arranged on the carrier member  12  and on the guide member  14 , with the respective servomotors being drivingly connected to the corresponding rotary parts  16 ,  18  via schematically indicated drive gears  30 . The rotary parts  16 ,  18  can be rotated with the servomotors  26 ,  28  in both rotation directions, either in the same direction or in opposite directions, causing the carrier member  12  to perform a pivoting or tumbling motion relative to the guide member  14  and thereby changes the toe angle and/or the camber angle of the wheel. 
       FIG. 2  shows schematically a cardanic coupling between the guide member  14  and the carrier member  12  which operates as an axial lock (holding the guide member and the carrier member together), as a rotation-lock, and as a torque support, for example, for braking torques and drive torques acting on the carrier member  12 . 
     For this purpose, articulated forks  32 ,  34 , which are offset with respect to each other by 90° and which are connected with each via bearing pins, commonly designated with  38 , and a supporting ring  40 , are attached to the guide member  14  and the carrier member  12 . The carrier member  12  can thus be cardanically pivoted about a vertical axis  42  and about an axis  44  perpendicular to the drawing plane, wherein the instantaneous center M of the cardanic connection is located at the intersection between the rotation axis  22  and the inclined rotation axis  24  of the rotary parts  16 ,  18 . 
     As already mentioned, the two rotary parts  16 ,  18  in  FIGS. 1 and 2  contact each other via planar inclined surfaces  16   b ,  18   b  to realize the inclined rotation axis  24 . Conversely, in the following  FIGS. 3 and 4 , the inclined rotation axis  24  of the rotary member  16  is not realized with the contacting planar inclined surfaces  16   b ,  18   b , but instead with conical inclined surfaces  16   b ,  18   b , which face each other with an interposed tapered roller bearing  84 . 
       FIGS. 3 and 4  show the structure of the wheel carrier  10  in a partial longitudinal section taken along the rotation axis  22  of the wheel of the wheel suspension, wherein the description is limited to the essential features of the invention. Functionally identical parts are denoted by identical reference symbols. 
     As described above, the wheel carrier  10  is composed of the guide member  14  which is connected for articulation relative to wheel guiding elements of the wheel suspension, such as control arms, etc., the carrier member  12  supporting the wheel (rim  46 ) and the rotary parts  16 ,  18 . 
     The guide member  14  has a support flange  48  which supports a radially inner bearing ring  50 . The bearing ring  50  forms via bearing rollers  52  in conjunction with the radially outer rotary part  18  a first roller bearing, whose rotation axis coincides with the rotation axis  22 . The outer bearing race  52   a  ( FIG. 4 ) of the tapered roller bearing  52  is ground directly into the rotary part  18 , which is for this purpose made of bearing steel and processed accordingly (hardened, etc.). 
     The rotary part  18  is further provided at its outer periphery with a spur gear  18   c  which drivingly cooperates via an unillustrated intermediate gear wheel with an unillustrated drive gear of the electric motor  28 , thus forming the toothed drive gear  30  depicted in  FIG. 3 . The electric motor  28  is hereby attached on the support plate  48  of the guide member  14 , on which the intermediate gear wheel is also supported for rotation. The rotary part  18  can be adjusted in both rotation directions with the electric motor  28 . 
     The carrier member  12  has a radially oriented flange section  58  and an axially extending hub section  60 . The hub section  60  is provided with an inner cone  60   a  ( FIG. 4 ) which widens toward the tapered roller bearing  52 . 
     In a simple plug connection, the outer cone  64   a  of a rotationally symmetrical bearing housing  64  of a tapered bead wheel bearing  66  having two ball rows  65  protrudes into the inner cone  60   a  of the hub portion  60  of the carrier member  12 . The wheel bearing  66  serves as a rotary bearing for a wheel flange  68 , on which in turn the wheel or the rim  46  and a brake disk  70  are attached with wheel bolts (not numbered). 
     Furthermore, the wheel flange  68  has a hub section  72  which extends approximately to the height of the tapered roller bearing  52  and receives the two inner bearing rings  66   a  of the wheel bearing  66  and which is fixedly connected via a spline  74  and a clamping sleeve  76  to the joint housing  78  of a cardan shaft (not shown in detail) driving the wheel. A central screw  80  supported on the wheel flange  68  and screwed into the joint housing  78  holds the entire assembly together in an axial direction. 
     The outer bearing races  66   b  of the wheel bearing  66  are ground directly into the bearing housing  64  made from bearing steel which protrudes into the inner cone  60   a  of the carrier member  12 . 
     Furthermore, the bearing housing  64  has an additional outer cone which is constructed with the opposite cone angle and directly forms the inner bearing race  82   b  for tapered rollers of a tapered roller bearing  82  for the second rotary part  16 . The rotary part  16  is also made from roller bearing steel and directly supports the outer bearing race  82   a  of the tapered roller bearing  82 . In addition, the rotary part  16  has radially outward the aforementioned inclined conical surface  16   b . This conical surface  16   b  cooperates via a tapered roller bearing  84  with the inclined conical surface  18   b  of the rotary part  18  to realize the inclined rotation axis  24  of the rotary part  16 . Respective inner and outer bearing races of the tapered roller bearing  84  are ground into the two conical inclined surfaces  16   b ,  18   b.    
     The tapered roller bearing  52  disposed between the adjusting ring  50  and the rotary part  18  and the tapered roller bearing  82  disposed between the bearing housing  64  and the rotary part  16  are arranged in an X-shaped bearing configuration (the cones of the inner bearing races  52   b ,  82   b  are arranged with a confronting taper), wherein the tapered roller bearing  82  is arranged rotationally symmetrically about the inclined rotation axis  24 . Conversely, the tapered roller bearing  52  is arranged rotationally symmetrically about the rotational axis  22 . A rotation of the rotary part  16  with the electric motor  26  and/or a rotation of the rotary part  18  with the electric motor  28  then cause the carrier member  12  to pivot relative to the guide member  14   
     The entire bearing assembly with the bearing housing  64 , the tapered roller bearings  52 ,  82  and  84  can be adjusted with a threaded ring  86  and preloaded. The threaded ring  86  is screwed into the support flange  48  of the guide member  14  via a threaded connection  62 . The threaded ring  86  operates to preload the adjusting ring  50  of the first tapered roller bearing  52 , which is displaceably guided in the support flange  48 , to the left. Accordingly, the entire bearing assembly  52 ,  82 ,  84  together with the bearing housing  64  of the wheel bearing  66  is preloaded from the right side of the drawing to the left side against the inner cone  60   a  of the hub portion  60  of the carrier member  12 . Due to the relatively large conical support base, an additional screw connection between the carrier member  12  and the bearing housing  64  of the wheel bearing  66  may be eliminated. 
     As already explained with reference to  FIG. 2 , a cardanic connection between the guide member  14  and the carrier member  12 , which is disposed radially outward of the rotary part  16 ,  18 , is also provided in the embodiment of  FIGS. 3 and 4 . The aforementioned bearing preload is axially supported by the cardanic connection, while the pivoting mobility of the carrier member  16  in relation to the guide member  14  is maintained when the rotary parts  16 ,  18  rotate. For sake of clarity, only the support ring  40  is shown in the cross-sectional drawing of  FIGS. 3 and 4 , while the articulated forks  32 ,  34  are not depicted. 
     To provide a low-weight construction of the described wheel carrier  10 , the components receiving the tapered roller bearings  52 ,  82 ,  84  and the wheel bearing  66 , as well as the bearing housing  64 , the rotary parts  16 ,  18 , the adjusting ring  50 , etc., are made from steel, whereas the less stressed guide member  14  and the carrier member  12  are made from a light metal.