Abstract:
A universal joint arrangement with a journal cross, supported by bearings in two joint yokes offset to one another by 90°. Each joint yoke comprises a flange and two bearings. Each bearing has an axial bearing mold element that is supported by a connection element on the joint yoke and at least indirectly on the journal cross to form a first and second friction pairing. The mold element has a planar face and a second face having at least one elevated support region facing the first or second friction pairing, and is arranged with the support region on the connection element, which elastically deflects under load. The regions on the second face other than the support region are free from contact with the connection element in every load state. The support region is arranged in the region of low relative movement of the connection element with the journal cross, while the regions other than the support region lie in the region of greatest relative motion.

Description:
This application claims priority under 35 USC §119 to currently pending German application number DE 10 2005 058 743.7, filed Dec. 8, 2005 by Voith Turbo GmbH &amp; Co. KG. The specification herein enclosed is a translation of the specification as filed with the German Patent Office. 
     FIELD OF THE INVENTION 
     The invention relates to a universal joint arrangement. 
     BACKGROUND OF THE INVENTION 
     Universal joint arrangements, in particular the bearing systems for suspension of the journal of a journal cross in joint yokes, for installation in propeller shafts are well-known in a number of designs for a multitude of application examples. Reference is made to the publication G 1757 d 08/02 1.000, “FEM-Simulation von Gelenkwellen mit inkompatiblen Netzen”, in which the problem of the deformations on the bearing and connection elements under load is disclosed. 
     Embodiments of universal joint arrangements are known for joint shafts, which comprise a journal cross which is supported by bearings in two joint yokes offset to one another by 90 degrees. The joint yokes themselves can be designed in one piece or in two pieces. For connection of the journal cross in the joint yoke a corresponding bearing arrangement is provided for the individual journals, which comprises a radial bearing and an axial bearing. In the process the radial bearings are always designed as anti-friction bearings (roller bearings), the axial bearings can be designed either as anti-friction bearings (roller bearing) or as friction bearings. For the arrangement of the axial bearing there are a number of possibilities, wherein however under consideration of the occurring deformations during the operation of the joint shaft a corresponding constructive layout of the individual elements of the suspension takes place. The problem of such a bearing arrangement lies in the fact that in the case of anti-friction suspension the individual anti-friction bearings, along with a high base torque, are additionally loaded by high torque impacts and simultaneous transversal accelerations, in particular in the case of use in rolling mill drives. These loads lead to elastic deformations of the joint yoke both in the region of the flange as well as also within the eye of the yoke. In reversing operation the deformations occur additionally with positive or negative value. These influences due to operation as well as design result in misalignments with an unfavorable load application in the bearing, namely a mismatch of the bore of the yoke, inclined position of the bore, spring deflection of the journal as well as a radial clearance in the radial bearing and the spring deflection of the anti-friction bearing, as is disclosed in the publication G 17 57 FIG. 12. The result is an uneven radial pressure distribution in the bearing bore, as a result of which locally high loads on the contact points of the anti-friction body of the radial bearing and excessive edge stresses arise. From the elastic deformations moreover relative movements between journal and bore of the yoke result in axial direction. If these relative movements are hindered by a too stiff bearing embedding, high constraining forces arise and with it high loads of the axial bearings, but only when the axial bearing is designed as an anti-friction bearing. In the case of anti-friction suspension this results in too high edge stresses in one segment of the axial bearing and in lifting of the rollers in the opposing segment. The unequal load results in a lessening of load bearing capacity. The constructive design, in particular the layout of the individual components, is in the process always to be adapted to the possible occurring deformation travels, so that it is not possible to provide a satisfying design independently of the knowledge of these influences. 
     One solution of this problem is known from the publication EP 1 167 796 B1 with an axial bearing in anti-friction bearing design. This is characterized by the special development of an axial bearing surface on a thrust ring. Here a free travel for the anti-friction elements is created solely through the development of the thrust ring on the basis of the worn material. The disadvantage of this design lies in the fact that the travel is consequently not to be predefined freely, but rather must be specified via the deformation travels determined in the case of specified operational load, as a result of which a complete rubbing contact of all anti-friction elements is not given for different loads, in particular in the partial load range and the negative consequences of the design according to the state of the art cannot be completely eliminated. 
     From DE 195 10 761 B1 a design of a journal bearing in bushing design anticipated as an axial bearing serves there as a thrust ring constructed as a plastic disk with elastic properties, which in the center exhibits a circular or circular-shaped limited contact surface protruding to the frontal area and near the edge an annular supporting surface, wherein the hollow spaces however only serve to absorb lubricants. 
     SUMMARY OF THE INVENTION 
     The invention is therefore based on the object of further developing a bearing system for universal joint arrangements of the initially named type, in particular for use in heavy propeller shafts in such a way that the named disadvantages can be prevented, i.e. said system exhibits a simple structure as well as a low number of components. The elimination of the negative influences in deformation of the torque transferring components to the bearing arrangement, in particular the axial bearing is to be achieved in the process independently from concrete types of load with the most standardized possible solution. The universal joint arrangement, in particular the bearing system and its individual elements should stand out in the process due to a low design and manufacturing expenditure as well as low costs. 
     A universal joint arrangement comprises a journal cross with two joint yokes offset to one another by 90 degrees and in reflected arrangement to the plane of symmetry of the journal cross located perpendicular to the joint axis. Each joint yoke comprises a flange part and two bearing parts, wherein each bearing part exhibits a bearing bore, in which the journals of the journal cross are supported. Each journal is in the process supported by means of a bearing arrangement, which comprises at least one radial bearing and one axial bearing, wherein the axial bearing is designed as a friction bearing. According to the invention the axial friction bearing comprises in accordance with a first solution attempt at least one separate axial friction bearing mold element which under formation of a first friction pairing supports itself at least indirectly on the joint yoke and a second friction pairing supports itself at least indirectly on the journal cross. The axial friction bearing mold element comprises a first plane frontal area and a second one which is characterized by at least one region of an elevation. The region of the elevation forms a support region, which in every function state forms a friction surface either of the first or second friction pairing. The axial friction bearing mold element is arranged in such a way that it rests without active operational load on the universal joint arrangement in the elevation region and elastically deflects under load in said elevation region, wherein the region outside of the elevation region at the first or second frontal area in every load state is free from contact with the connection elements. The elevation range forming a first support region is, referring to conventional solutions, arranged as it were in the region of low relative movements and with it of low elastic deformation, while they lie on the elevation range adjoining this free region in installation position in the region of greatest relative motion. This means that in regions of greatest relative movements even under load a resting of both sides on the axial friction bearing mold element is prevented and with it elastic deformations there can be eliminated. 
     The region of greatest axial relative movements is located in a cross-sectional plane perpendicular to the joint axis through the respective journal axis. On the side of the relieved radial bearing on this plane the relative movements are enabled by the recesses on the axial friction bearing mold element free from distortion. On the opposing side in the high pressure region of the radial bearing the axial bearing elements stand out from each other. 
     In accordance with a second solution attempt the axial friction bearing comprises a conventional axial friction bearing pressure disk and supports itself on a correspondingly molded connection element. The shaping corresponds in the process to the shaping described for the axial friction bearing mold element in the first solution attempt. Here too there are partial elevations provided on a frontal area of at least one connection element. This is achieved by means of molding in the case of shaping or production or reworking of the respective connection element or by subsequent connection to correspondingly molded elements, for example by means of material closure. In this case for example corresponding modifications are made to
         a) the bearing bore, in particular in the case of design as a blind hole on the frontal area facing the journal   b) the journal frontal area   c) the bottom of the bearing bushing for the radial bearing or the bearing lid       

     These are preferably determined by a rotationally symmetrical design, i.e. an elevation, wherein the elevation is characterized viewed in cross-section by constant dimensions in axial direction and viewed perpendicular to it however by changing dimensions. By axial direction in the process the direction of the journal axis is understood. 
     With the solution according to the invention hence a partial elastic form closure is always realized, which even under the influence of high axial forces does not result in a damage of the bearing or of the connection elements. The known negative effects from the state of the art on the basis of the relative movements are compensated for in this connection by the form of the axial friction bearing mold element or of the connection element. Said connection element is in the process developed in such a way that it exhibits first regions, which are also termed as support regions, which are arranged preferably symmetrically on the element—axial friction bearing mold element or connection element—and in essence lie in the region of the plane, which is characterized by the journal axis and the joint axis or which extend on both sides from this plane in circumferential direction of the journal. These regions are in the process characterized by regions of greater cross-sectional areas, compared to the cross-sectional areas of the adjoining, inactive regions which are formed with the recesses. The enlargement of the cross-sectional area takes place viewed in installation position in the direction of the journal axis. In the regions of greater cross-sectional area a free of play resting against the connection elements always takes place, while in the inactive regions a resting is always prevented with certainty. I.e. in the regions of great relative movement recesses (material removal) prevent a resting of the connection elements under operational load. Through this shaping, which is realized as it were by material reductions in specified regions on the axial friction bearing mold element or the connection element, clearance is thus created for the relative movements of the connection elements occurring due to the deformation. This relates in particular to the connection elements for the radial bearing or the joint yoke. The cross-sectional difference or the material removals are in the process designed in such a way that even in the regions of greater relative movement no contact is given at least on one of the two frontal areas of the axial friction bearing mold element or of the axial pressure disk with the connection elements. 
     With regard to the installation situation of the axial friction bearing in essence two different relative positions are distinguished. A first position is characterized by the arrangement in the region of the journal root and a second one in the region of the journal frontal area. Depending on these arrangement possibilities differing development possibilities of the solution attempts also result. In the process symmetrical designs, in particular rotationally symmetrical, and non-symmetrical are distinguished. This applies both for the first solution attempt as well as for the second solution attempt. 
     In the simplest case in accordance with the first solution attempt the axial friction bearing mold element is designed as an annular or disk-shaped element, wherein said element exhibits a first frontal area forming a plane surface and a second frontal area, on which elevations for the formation of the support regions are provided. In the process a design as an annular element is used, in particular in the case of the arrangement of the axial friction bearing in the region of the journal root. Preferably the annular or disk-shaped element is in the process developed in such a way that it is designed rotationally symmetrically with regard to two axes perpendicular to each other. With this two support regions and two inactive regions result on the axial friction bearing mold element, wherein in this case the axial friction bearing mold element can be used regardless of the rotational direction of the universal joint arrangement, i.e. is designed for both rotational directions. The support regions for slight elastic spring deflection in the case of small relative movement are in the process arranged in essence in the region of a plane, which is characterized by the respective journal axis and the joint axis and extend proceeding from this plane on both sides over a sub-region in circumferential direction of the journal. The material recesses, i.e. the regions of lower cross-section are in the process arranged in the areas of the highest or greatest relative movement. High loads of the connection elements are intended to be eliminated through the solution in accordance with the invention. The regions of the greatest relative movement are in the process characterized by an angular range in the journal cross-section, proceeding from a plane that can be described as perpendicular to the joint axis through the journal axis, from said axis in circumferential direction of the journal in both directions in each case in an angular range of 45°&lt;α&lt;60°, preferably α˜60°. The ranges of greater relative movement of the bearing connection elements hence extend in an angular range on both sides of a plane of symmetry through the journal axis and the joint axis. The regions in the region of the plane, which is clamped by the joint axis and the journal axis or lying on both sides of it, are termed as the regions of lower relative movement. Their location is characterized by the describable plane arranged through the journal axis and the joint axis and extends on both sides proceeding from it in circumferential direction of the journal or the bore of the joint yoke. 
     Regarding the cross-sectional shaping of the axial friction bearing mold element itself there are no restrictions whatsoever. Decisive is only the fact that a material removal is provided here in the high-load regions in the case of conventional solutions. 
     For the designs with arrangement of the axial friction bearing mold element in the region of the journal frontal area a number of geometries are also conceivable. The element can be designed symmetrically here also. However, a shape deviating from the symmetrical design is also conceivable. However, in any event it is to be ensured that a fixing of location takes place in circumferential direction. This can be realized by form closure or adhesion force. In the case of a form fit design the axial friction bearing mold element is centered in a recess on the journal frontal area, the joint yoke, a cover element or the floor of a radial bearing bushing. Here too preferably one frontal area is always plane and the other second frontal area is characterized by an elevation. The one frontal area in the process rests plane against one of the connection elements, while the other one rests only in the support region on the connection element. The elevation region extends in the process preferably over the entire element in the direction of depth, i.e. as it were on a plane which is characterized by the journal axis and the joint axis over the entire journal frontal area. The elevation itself can be designed in this direction as a constant cross-section or with cross-sectional changes. In the process emphasis is placed here also on a symmetrical design in installation position parallel to the joint axis in order to guarantee the free exchangeability and the independence with regard to the rotational direction in the case of installation. In the view in the direction of the journal axis concave or convex or other type cross-sectional contours result over the direction of extension viewed on the plane which can be described by the journal and joint axis in installation position. 
     The axial bearing mold element exhibits for an arrangement in the region of the journal frontal area a plane frontal area and a second frontal area at which the support region is arranged. The base geometry, i.e. the geometry of the plane frontal area is preferably determined by a circular contour, however any other geometry is also conceivable. In the case of deviation from the circular contour the lateral surfaces could be used as centering surfaces, if corresponding complementary recesses or contact surfaces for the centering surfaces are provided on the connection elements, in particular of the journal frontal area. The elevation itself is preferably designed symmetrically in relation to the plane through the joint and respective journal axis and extends along said axis over the entire dimension of the axial friction bearing mold element in this direction. 
     Preferably the height of the elevation along the plane of journal axis and joint axis and perpendicular thereto is constant. However soft or rounded (or inclined designed) transitions to the regions free from the elevation are also conceivable. 
     Preferably the external geometry of the individual axial friction bearing mold elements is selected in such a way that said geometry corresponds to the connection elements with regard to contour and dimensioning at least at the flat circular frontal area. In particular this means that preferably the axial friction bearing mold element is designed with the diameter which corresponds either in the case of arrangement on the journal root to the external diameter of the external ring of the radial bearing or in the case of arrangement on the journal frontal area with the diameter which corresponds to the journal diameter. Other designs are conceivable. However, preferably the greatest possible dimension regions are always selected for areal resting of the plane frontal area, in order to guarantee an optimum load bearing performance. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS. 
       The solution according to the invention will be explained in the following with the help of figures. The figures show the following: 
         FIG. 1  illustrates the effects of deformation and axial distortion of journal cross and joint yoke under load in the design of bearing bushing with convention (plane) axial pressure disk (thrust washer); 
         FIGS. 2 and 2   a  illustrate with the help of an axial section through a universal joint arrangement an arrangement of an axial friction bearing mold element according to the invention in accordance with the first solution attempt in the region of the journal root; 
         FIGS. 3   a  through  3   c  illustrate a possible design of an axial friction bearing mold element according to  FIG. 2 ; 
         FIG. 4  illustrates an arrangement of an axial friction bearing mold element in the region of the journal frontal area for support on this and on a bearing bushing; 
         FIGS. 5   a  through  5   c  illustrate possible geometry developments of the axial friction bearing mold element in the region of the elevation; 
         FIGS. 6   a ,  6   b   1 ,  6   b   2  and  6   b   3  illustrates an alternative design to  FIG. 4 ; 
         FIGS. 7 and 8  illustrate a possible development of an axial friction bearing mold element for direct support on the joint yoke or a bearing cover; 
         FIG. 9  illustrates a first design in accordance with the second solution attempt; 
         FIG. 10  illustrates a second design in accordance with the second solution attempt. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  illustrates in greatly exaggerated representation of the deformations of the components in a prior art universal joint system  1 ′, the problem underlying the solution according to the invention of the effect of relative movements in axial direction of the journal on the bearing system of a journal cross  3 ′ of a joint yoke  6 ′ with the help of a section from an axial section through the journal cross  3 ′. Represented in exemplary fashion is a journal  4 ′ having an axis Z 4 ′, which is supported by bearings via a bearing system  10 ′ in a joint yoke half  6 . 1 ′. Further recognizable is a bearing part  8 ′ of the joint yoke half  6 . 1 ′. The bearing system  10 ′ comprises a radial bearing  13 ′. In the represented case the inner bearing track of the anti-friction elements  15 ′ of the radial bearing  13 ′ is formed by the generated surface  16 ′ of the journal  4 ′. The exterior bearing surface is formed by a bearing bushing  45 ′. In the case of torque transfer the circumferential force causes an uneven load of the radial bearing  13 ′, i.e. in the direction of the circumferential force very high edge stresses and on the opposing side a play between the anti-friction elements  15 ′ and the connection elements bearing bushing  45 ′ or journal  4 ′. This applies in analogy also for the represented axial friction bearing  46 ′ designed as two-sided plane thrust washer, which in accordance with the design of  FIG. 1  is arranged for example between journal front side  36 ′ and the inner circumference of the bearing bushing  45 ′. 
     Through the spring deflection of the journal cross in the radial bearing great relative movements arise in axial direction of the journal, which in the case of form fit installation position generate high compressive forces on the axial friction bearing mold element  46 ′ plane on both sides and the bushing floor. High loads result from this, in particular in the notch regions of the bearing bushing. 
     It can be recognized that the axial friction bearing  46 ′ in the case of arrangement on the journal front side  36 ′ viewed in the direction of the circumferential force in the region of a plane of the axial section through the universal joint arrangement does not support, while the opposing region is subject to very high compressive forces. 
       FIGS. 2 and 2   a  illustrate in schematically simplified representation with the help of a segment from an axial section (this segment divided at the midpoint of axis Z 4,5  into  FIGS. 2 and 2   a ) through a universal joint arrangement  1  the integration of an axial bearing  17  shaped in accordance with the invention. The universal joint arrangement  1  comprises for this purpose a journal cross  3 , which is supported by bearings with its four journals offset from each other by 90° , here by way of example only  4  and  5  (shown in  FIG. 2   a ) in one joint yoke  6 . The joint yoke  6  is for this purpose designed in one piece or two pieces depending on the design of the bearing support structures. The separation takes place in the process preferably centrally in a plane of symmetry perpendicular to the axis of the bearing bores in the flange part  7 , wherein the individual joint yoke halves  6 . 1  and lying opposite here  6 . 2  (shown in  FIG. 2   a ) are then characterized by a flange part  7 . 1  and  7 . 2  (shown in  FIG. 2   a ) and each joint yoke half  6 . 1  and  6 . 2  comprises a bearing support structure. The bearing support structures  8  and  9  (shown in  FIG. 2   a ) may have bearing bores, represented here by way of example in the form of a blind hole or pocket hole bore  12  for the joint yoke half  6 . 1 , in particular for the bearing support structure  8 . 
     The joint yoke arranged offset by  90 ° and the journals supported by bearings within are not shown. The only bearing system  10  comprises in the process a radial bearing  13 . This is preferably designed as an anti-friction bearing, wherein the outer bearing surface is formed by way of example for the anti-friction elements  15  by a retaining ring  14 . The inner bearing surface for the anti-friction elements  15  is formed for example by the generated surface  16  of the journal  4  supported by bearings in the bearing support construction  8 . In addition the bearing system comprises an axial bearing  17  which comprises in accordance with the invention an axial mold friction bearing element  2 . This is arranged in accordance with  FIG. 2  in the region of the journal root  18  of the journal  4 . In the process the axial mold friction bearing element  2  forms with the connection elements  21 ,  22  friction pairings  20 . 1  and  20 . 2 . In the process the individual friction surfaces on the connection elements  21 ,  22  are formed by the retaining ring  14  of the axial bearing  17  and a bearing flange  23 . The axial mold friction bearing  2  supports itself in the process on the bearing flange  23 , which in turn supports itself on the journal cross  3 , in particular the journal root  18 . In the process in the represented case the frontal area facing in the direction to the joint axis G of the retaining ring  14  of the radial bearing  13  forms a friction surface and the axial friction bearing form element  2  forms the additional friction surface of the friction pairing  20 . 1 . Further a second friction pairing  20 . 2  is provided here, which is formed out of the axial mold friction bearing element  2  and the bearing flange  23 . 
     The concrete design of the axial mold friction bearing element  2  is reproduced in  FIG. 3 .  FIG. 3   a  illustrates in the process a perspective view, while  FIG. 3   b  reproduces in schematically simplified representation a view from above and  FIG. 3   c  reproduces a view from the front. The design of the axial mold friction bearing element  2  shown in  FIGS. 3   a  through  3   c  is exemplary. Said element is designed as annular element  28 , which is characterized by a special shaping, in which case the elastic deformations only occur in the region of small relative movements. As a result of the significantly higher flexibility no high distortions arise. In the regions with great relative movements distortions are prevented by material recesses. Plastics are used as material, in particular elastomers which are characterized by a modulus of elasticity in the range of 5000 to 20000 N/mm 2 , preferably 5000 to 10000 N/mm 2 . The axial mold friction bearing  2  is characterized by at least two regions of differently designed out cross-sections. Preferably the arrangement takes place in such a way that the regions of different cross-sections viewed in installation position symmetrically related to the journal axis, which coincides with the center axis M of the annular element  28 , are arranged so that in installation position in a universal joint arrangement the function is guaranteed regardless of the rotational direction of the universal joint arrangement.  FIGS. 3   a  through  3   c  illustrate in the process an axial mold friction bearing element  2  that can be used in such a way for normal operation and reversing operation. For this purpose said element exhibits related to a first line of symmetry S D  extending through the theoretical center point M on a plane through the joint and respective journal axis. For this purpose two symmetrical regions  29  and  30  are arranged, which form in the case of low relative movement of the connection elements form adapting load bearing regions or support regions of the axial bearing in loaded state under the effect of circumferential force. These support regions  29  and  30  are designed identically with regard to the choice of their cross-section and form on the basis of their geometry regions with elevation compared to the remaining cross-sectional regions. The development of the support regions  29 ,  30  exhibits a symmetrical structure in addition to a line of symmetry S DS  aligned perpendicular to the line of symmetry S D  and running through the center point M. 
     The regions  31  and  32  form recesses and are characterized by smaller cross-sectional dimensions than the support regions. The recesses extend uniformly in circumferential direction of the annular element  28  proceeding from the line of symmetry S DS  over a region α. Outside of the angle α in circumferential direction the transition to the regions  29  and  30  occurs proceeding from the line of symmetry S DS , said regions only experiencing a slight compressive stress in the case of spring deflection. The support regions  29  and  30  are in the process always active and characterized by a cross-sectional reinforcement in elevation direction. The inactive regions  31 ,  32  are allocated in installation position to the regions with great relative movements and still exhibit a play even under high operational load. The installation in the universal joint arrangement in accordance with  FIG. 2  takes place now in such a way that the support regions  29  and  30  are arranged on a plane through S D , the regions  32  and  31  on the plane through S DS . 
     The spring deflection of the journal cross  3  in the radial bearing  13  causes an uneven distribution of force in the axial bearing  17 , wherein in the design as an anti-friction bearing only a fraction of the theoretical load bearing capacity can be used. The lacking plane parallelism of the axial bearing surfaces results in a premature fatigue or wear and tear. On the other hand however the assured dynamic and static load capacities are only guaranteed in a rigid bearing connection design. In order in spite of this to compensate the occurring relative movements between axial bearing  17  and bearing connection elements, the axial mold friction bearing  17  is integrated into the universal joint arrangement in such a way that on the basis of the existing differing cross-sections in circumferential direction an areal resting against the frontal area of the radial bearing shell is only given in the regions of low relative movement. The solution according to the invention is in the process characterized by the fact that the axial mold friction bearing  2  under load enables a partial elastic form closure with the elevation regions. In the regions in which the relative movements are small, a soft spring deflection is enabled, while in the regions with great relative movement free travels are provided which even under load are not completely exhausted, i.e., the recesses guarantee axial relative movements between joint yoke G and journal cross without buildup of elastic deformations in the bearing components. The transition between the regions of differing cross-sectional geometry and/or dimensions takes place in the process either continuously or in stages. 
     In the region of the elevations the only slight relative movements cause elastic deformations of the axial friction bearing mold elements, the material recesses on the axial friction bearing mold element enable great, contact-free relative movements. Through the choice of a plastic, in particular elastomers, with a modulus of elasticity of 5,000-10,000 N/mm 2  only slight distortion forces or compressive stresses arise in the axial bearing. 
     The axial bearing  17  in accordance with  FIG. 3   a, b , in particular the axial friction bearing mold element  2 , is installed in the universal joint arrangement according to  FIG. 2  in the manner that the support regions  29  and  30  extend in an angular range between  30 ° and  45 ° , preferably ca.  30 °, from a plane determined by the joint axis G and the respective journal axis through the axis of symmetry S D . The elevation region is preferably given only in one direction, i.e. on one plane frontal area  20 , so that on the opposing plane frontal area  24  an areal resting over the entire circumference against the connection element  22 , here the bearing flange  23 , is given. 
       FIG. 4  illustrates an additional possible arrangement of an axial bearing  417  and a universal joint arrangement  401 . In the case of this design the arrangement takes place on the front side  436  of the journal  404  supported by bearings in the corresponding joint yoke  406 .  FIG. 4  represents in the process a first possible embodiment in which the connection element  421  is formed by a bearing bushing  445 , while the other bearing connection element  422  is formed by the journal  404 . The axial friction bearing  419  is arranged here between the retaining ring  414  of the radial bearing  413  and the frontal area  436  of the journal  404 . The friction pairings  420 . 1 ,  420 . 2  are also formed between these elements. For this purpose the axial mold friction bearing element  402  is designed as an annular or disk-shaped element, wherein the shape of a disk is preferred. The disk is designed circular with regard to the geometry on the outer circumference and comprises a non-rotationally symmetrical support region. Viewed in axial section this region extends over a width B in the form of a projection  438 , which rests free of play. The alignment of the support region  437  formed by the projection  438  occurs in the process also here preferably again on both sides to the line of symmetry S D  on the plane through the journal axis Z 4,5  and the joint axis G. The corresponding material recess is located in the process on the frontal area  439  of the axial friction bearing mold element  417  facing the journal cross. The support region  437  in the form of the projection  438  is not designed rotationally symmetrically, but rather extends with a width B over a predefined length I, preferably the entire extent of the axial friction bearing mold element  402  along the line of symmetry S D . The represented elevation in the support region  437  can be limited by plane or curved areas of contact perpendicular to the axial direction. Possible designs are reproduced in greatly simplified representation for a view of the bottom on the axial friction bearing mold element  402  in the direction of the journal axis in accordance with  FIG. 4  in  FIGS. 5   a  through  5   c . These show views of the bearing frontal area with the support region  537   a ,  537   b , and  537   c  of the axial friction bearing mold element  502   a ,  502   b , and  502   c . From this it can be seen that the support region  537   a ,  537   b , and  537   c  extends over the entire dimension parallel to the line of symmetry S D . In the process  FIG. 5   a  illustrates a design with constant width B of the projection  538   a  along or on both sides of the axis of symmetry S D , i.e. parallel frontal areas of the projection, while  FIG. 5   b  reproduces a development with concave and  FIG. 5   c  shows a development with convex geometry related to the expansion along the line of symmetry S D . 
       FIG. 6   a  illustrates a design of the axial friction bearing mold element  602  in which the material recess is located on the frontal area of the journal  604  in installation position facing the bushing bottom. The bushing bottom  640  forms in the process a first friction surface for the axial mold friction bearing element  602 , while the second friction surface of the friction pairing  620 . 1  is formed here by the frontal area  641  of the axial friction bearing mold element  602 . This applies in analogy for the friction pairing  620 . 2 , which is provided between the axial friction bearing mold element  602  and the front side  636  of the journal  604 . In the process preferably the axial friction bearing mold element  602  is also arranged for the purpose of its centering in a corresponding recess on the front side  636  of the journal  604 . Preferably however it is not a matter of a cylindrical bore here, but rather a groove  644 , which simultaneously assumes the centering function for the axial friction bearing mold element  602 , i.e. locally fixes the location of the axial friction bearing mold element  602  in the direction of the circumferential force. The width of the groove and with it the extent of the axial friction bearing mold element  602  on the plane perpendicular to the rotational axis of the joint through the journal axis amounts to about the half of the journal diameter. With it in the region of the great axial relative movements corresponding free spaces result between journal frontal area  636  and bushing bottom  640 . The axial friction bearing mold element  602   a ,  602   b , or  602   c  is for this purpose by way of example as in  FIGS. 6   b   1 ,  6   b   2  represented as a plate-shaped element which by way of example possesses a rectangular base geometry and which exhibits an elevation region  637   a    637   b , or  637   c  on its front sides which in installation position forms a first support region. According to  FIG. 6   b   3  the groove for centering of the location of the axial friction bearing mold element  602   c  runs parallel to the line of symmetry S D . As already stated, a circular or cylindrical development of the axial friction bearing mold element  602  is also conceivable, wherein in this case other means for location fixing would be provided. The arrangement occurs in the process free of play between the journal  604  and the bushing bottom  640 , wherein corresponding to the relative movements only a slight spring deflection takes place on the basis of the geometric development in the region of the frontal area  641  of the axial friction bearing mold element  602 . The designs shown in  FIGS. 6   b   1  through  6   b   3  are exemplary. A development of the elevation region as shown in  FIGS. 5   a  through  5   c  is also conceivable. 
       FIG. 7  illustrates on the other hand an alternative design according to  FIG. 6  with the design of the axial bearing in a blind hole in the case of direct support on the journal yoke half  706 . The axial bearing  717  is hence arranged here directly between the joint yoke  706  and journal  704 . Regarding the design there are again also several possibilities. Preferably the axial friction bearing mold element  702  is designed as a cylindrical disk, wherein said disk is designed in the center region, i.e. on both sides of the line of symmetry S D , with a corresponding elevation. This can extend over a sub-region of the radial extent of the disk element or, as shown here, preferably over the entire dimension parallel or inclined or curved compared to the line of symmetry S D . The support region  737  is in the process directed to the joint yoke  706 . The opposing plane front side rests areal against the frontal area  736  of the journal  704 . The regions  731 ,  732  free from the elevation are arranged in the regions of greater relative movement. This, in particular the front side of the axial friction bearing mold element  702  bearing the elevation, forms a free space with the joint yoke G in the process in the regions of great relative movement. The elevation or support region  737  can be designed cylindrical or by way of example corresponding to the designs in  FIGS. 5   a  through  5   c.    
     In contrast  FIG. 8  illustrates a development of the axial friction bearing mold element  802  with support between journal front side  836  and the bottom of the yoke bore  849  or a differently developed bottom, for example in the form of a bearing cover, wherein here the support region  837  is directed to the front side  836  of the journal  804  and supports itself on it. 
     In  FIGS. 7 and 8  the axial friction bearing mold element  702  or  802  is designed disk-shaped or annular, wherein the disk-shaped or annular element comprises a first front side characterized by a plane surface and the support region  737  or  837  provided for elastic spring deflection is designed on the second opposing frontal area. The support region  737  or  837  resting free of play on the connection element in all function states is in this case not rotationally symmetrical, but rather is designed for example similar to the representations described in  FIGS. 5   a  through  5   c . It is also conceivable to design the support regions  737 ,  738 ,  837 , or  838  not in one piece, but rather segmented. 
     If  FIGS. 1 through 8  illustrate designs with separate axial friction bearing mold element  2 , this function can in accordance with  FIGS. 9 and 10  in accordance with a second solution attempt be assumed by the connection elements joint yoke  906 , journal  904 ,  905  and/or bearing bushing, i.e. the function of the axial friction bearing mold element  2  is then executed directly by these elements. 
     In accordance with  FIG. 9  the axial bearing  917  comprises an axial bearing pressure disk  946  as in the case of designs according to the state of the art, preferably with plane front side  947 ,  948  on both sides. The function of the axial friction bearing mold element is assumed in accordance with  FIG. 9  by way of example by the bearing bushing  945 , in particular the bushing bottom  940 . An assumption of function by the joint yoke  906  in particular the closed bearing bore  949  is also conceivable. 
     The support region  950  in the form of the elevation  951  is in the process correspondingly incorporated in the bushing bottom  940 . Preferably this takes place by removal of material for example grinding. Regarding the design of the elevation  951  a multitude of possibilities exists with the restriction that as a result of the rotation of the bearing bushing in operation a rotationally symmetrical shaping is to be selected. Decisive is the fact that only the center region of the bushing bottom  940  is active by elevation as a support region  950  and the outer regions of the bushing bottom  940  form free spaces to the journal front side  936 . These free spaces enable relative movements without causing axial distortions on the connection elements. 
       FIG. 10  illustrates an addition design in integral style on the journal  1004 , in particular the frontal area  1036 . Here the support region  1050  is formed by an elevation region  1051 , which is designed in installation position with its axis of symmetry SD parallel to the joint axis G. These support regions can be formed by one surface or a multitude of individual segment-type surface regions, designed spaced apart from one another. 
     The support takes place directly or via an axial bearing pressure disk  1046  as in the case of the designs according to the state of the art. 
     The design of the elevation region  1051  on the journal frontal area can also take place variably. In the simplest case in turn by corresponding material removal. Regarding the geometrical development there are also a multitude of possibilities. These can be designed viewed in cross-section rounded or with sharp edges. Further they can be designed rotationally symmetrical in a view from above with regard to the journal axis or with regard to an axis perpendicular to the journal axis running parallel to the joint axis. 
     Reference List
       1  Universal joint arrangement     2  Axial friction bearing mold element     3  Journal cross     4 , 5  Journal     6  Joint yoke     6 . 1 ,  6 . 2  Joint yoke half     7  Flange part     8 , 9  Bearing part     10 , 11  Bearing system     12  Bearing bore     13  Radial bearing     14  Retaining ring     15  Anti-friction element     16  Generated surface of the journal     17  Axial bearing     18  Journal root     19  Axial friction bearing     20  Frontal area     20 . 1 , 20 . 2  Friction pairing     21  Connection element exterior     22  Connection element interior     23  Bearing flange     24  Frontal area     25  Friction pairing     26  Centering device     27  Seal retainer     28  Annular element     29  Support region     30  Support region     31  Region recess     32  Region recess     33   1   st  frontal area axial bearing mold element     34   2   nd  frontal area axial bearing mold element     35  Surface     36  Front side     37  Support region     38  Cone, projection     39  Front side     40  Bushing bottom     41  Front side     42  Friction pairing     43  Journal bore     44  Groove     45  Bearing bushing     46  Axial bearing pressure disk as thrust washer     47  Front side     48  Front side     49  Bearing bore     50  Support region     51  Elevation   S DS  Line of symmetry   S D  Line of symmetry   a Distance from the axis of symmetry in circumferential direction   Z 4,5  Journal axis   G Rotational axis of the joint shaft   α Angle of circumference recess   B Width of the support region   b Thickness of the axial friction bearing mold element   h Height of the support region of the axial friction bearing mold element   

     ΔS Height difference between support region and recessed region of axial friction bearing mold element