Abstract:
A plate-link chain for a continuously variable transmission of a motor vehicle. The chain includes relatively long and relatively short chain links. In long-short regions the chain links are arranged to overlap in a chain running direction by arranging plate-links disposed adjacent to one another transversely with respect to the chain running direction, and coupled to one another by pairs of rocker pressure members. In the long-short regions the plate-links of the chain links are arranged in a double configuration or in a triple configuration. Spacing or biasing elements are provided between pairs of side-by-side plate-links to provide damping of the plate-link chain when in operation.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application is the U.S. national phase application under 35 U.S.C. §371 of International Application Serial No. PCT/DE2013/200294, having an international filing date of 11 Nov. 2013, and designating the United States, which claims priority based upon German Patent Application No. DE 10 2012 222 007.0, filed on 30 Nov. 2012, the entire contents of each of which applications are hereby incorporated by reference herein to the same extent as if fully rewritten. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to a plate-link chain, in particular for a continuously variable transmission of a motor vehicle. The chain includes relatively long and relatively short chain links, which are arranged in long-short regions to overlap in a chain running direction. The relatively long and relatively short plate-links are disposed adjacent to one another, transversely with respect to the chain running direction, and are coupled to one another by pairs of rocker pressure members. 
         [0004]    2. Description of the Related Art 
         [0005]    From the German published application DE 100 36 258 A1 a plate-link chain for a continuously variable transmission of a motor vehicle is known, which is made up of individual chain links that are connected to one another by articulation devices. Each of the chain links has a plurality of plate-links disposed essentially parallel to each other, at least part of the chain links having different plate-links with at least one first type of plate-link and at least one second type of plate-link. From the German published application DE 199 51 949 A1 a plate-link chain is known having a plurality of link plates which are hingedly connected with one another by means of pressure members, the pressure members running transversely to the longitudinal direction of the chain. A deflection of the plate-link chain in at least one direction transverse to its running direction to damp pressure vibrations is subject to resistance. 
         [0006]    An object of the present invention is to optimize a plate-link chain, in particular with regard to undesired swing-back during operation. 
       SUMMARY OF THE INVENTION 
       [0007]    The object is achieved by a plate-link chain, in particular for a continuously variable transmission of a motor vehicle, that includes relatively long and relatively short chain links. In long-short regions the chain links are arranged to overlap in a chain running direction and include relatively long and relatively short plate-links disposed adjacent to one another transversely with respect to the chain running direction, and coupled to one another by pairs of rocker pressure members. The plate-links of the chain links are arranged in a double configuration in the long-short regions, and otherwise in a triple configuration. The double configuration is also known as a two-plate grouping. Similarly, the triple configuration is known as a three-plate grouping. The longer and the shorter chain links have various pitches in order to enable so-called randomization. The pitch of the larger chain links is large enough so that two plate-link sets of the shorter chain links fit between the rocker joints. According to an essential aspect of the invention, the longer chain links deviate from the triple pattern. Instead, the plate-link pattern is mirrored in the respective longer chain link; that is, the following chain link has the same plate-link arrangement as the preceding one. As a result, the plate-links lie in the same position and contact one another at the corresponding outside contour. 
         [0008]    One preferred exemplary embodiment is characterized in that in the long-short regions, the plate links of preceding and following chain links in the chain running direction are arranged in a line so that the plate-links contact one another with their ends that face one another. The terms preceding and following refer to the introduction of power or torque in the operation of the chain. The pairs of rocker pressure members each include two rocker members which, together with the plate-links, constitute rocker joints. The longer and shorter chain links include different types of plate-links. According to one aspect of the invention, the long-short region can be represented with just two types of plate-links. This provides, in particular, the advantage that overlap tips, which would otherwise be necessary, can be dispensed with. 
         [0009]    Another preferred exemplary embodiment of the plate-link chain is characterized in that outside contours of the mutually abutting ends of the chain links are shaped so that a deflection of the plate-link chain in a straight strand transverse to the running direction of the chain, in particular in an upper region, is prevented. The outside contours of the mutually abutting ends of the chain links, in particular of mutually abutting plate-link sets of the shorter plate-links, are preferably shaped in the upper region so that those plate-links are in contact with one another in the straight strand and prevent swing-back. 
         [0010]    Another preferred exemplary embodiment of the plate-link chain is characterized in that transverse to the chain running direction intermediate spaces are left free between plate-links of the longer and plate-links of the shorter chain links. Transverse means crosswise to the chain running direction. The intermediate spaces are filled with the following functional options, which can be combined with one another in any manner desired. According to one variant, the intermediate spaces can be filled with defined masses, in order to ensure homogeneous weight distribution by equalizing the weight. According to another variant, to damp the joints the intermediate spaces can be filled with elastic elements which are beneficially biased before being placed around the rocker joints. According to another variant, the plate-links can be biased against one another by filling the intermediate spaces transversely to the chain running directions. This improves the damping of the plate-link chain. According to another variant, the plate-links can be biased in the chain running direction against neighboring rocker pressure pieces in order to improve the elasticity or damping of the plate-link chain. According to still another variant, the plate-links can be biased in the chain running direction against one another, which improves the elasticity or damping of the chain. 
         [0011]    The intermediate spaces can be completely or partially filled to constitute the previously described variants. For the stated purposes, the intermediate spaces can be completely or partially filled with intermediate elements made of an elastomeric material, such as rubber or a rubber-coated fabric. Alternatively, or additionally, the intermediate spaces can be completely or partially filled with sheet metal material, in particular corrugated, and/or with shaped wire spring material. The material which completely or partially fills the intermediate spaces can be integrally connected to the plate-links as a single piece. 
         [0012]    Another preferred exemplary embodiment of the plate-link chain is characterized in that spacing and/or biasing elements are disposed in the intermediate spaces. The spacing and/or biasing elements are preferably operative in the chain running direction and/or transversely, i.e., crosswise to the chain running direction. 
         [0013]    Another preferred exemplary embodiment of the plate-link chain is characterized in that the spacing and/or biasing elements are supported in the intermediate spaces in the chain running direction and/or crosswise to the chain running direction. The support beneficially enables unwanted vibrations in the operation of the plate-link chain to be prevented, or at least significantly reduced. 
         [0014]    Another preferred exemplary embodiment of the plate-link chain is characterized in that the spacing and/or biasing elements are made from a corrugated spring material. The corrugated spring material enables biasing transverse to the chain running direction to be effective in a simple manner. The corrugated spring material can also enable biasing to be effective in the chain running direction. 
         [0015]    Another preferred exemplary embodiment of the plate-link chain is characterized in that the spacing and/or biasing elements are made from a corrugated spring material. Depending on the design, the spacing and/or biasing elements can be provided with indentations and/or cutouts. 
         [0016]    Another preferred exemplary embodiment of the plate-link chain is characterized in that the longer chain links each include two inner and two outer plate-links. The terms inner and outer refer to the transverse direction, i.e., crosswise to the chain running direction. In the middle, two longer plate-links of the longer chain links are disposed side-by-side or parallel, crosswise to the chain running direction. On the outside in each case, a longer plate-link of the longer chain links is spaced from the inner plate-links, crosswise to the chain running direction. 
         [0017]    Another preferred exemplary embodiment of the plate-link chain is characterized in that crosswise to the chain running direction, between the inner and the outer plate-links of the longer chain links; in each case four identical plate-links of the shorter chain links are disposed. The four identical plate-links of the identical chain links are combined in each case into two pairs of plate-links. 
         [0018]    The invention also relates to a spacing and/or biasing element for a previously described plate-link chain. The spacing and/or biasing element can be marketed separately. 
         [0019]    The invention also relates to a chain-driven conical-pulley transmission having a previously described plate-link chain. The chain-driven conical-pulley transmission is also referred to as a CVT or continuously-variable transmission. 
         [0020]    The plate-link chain according to the invention is a plate-link chain for a continuously variable transmission of a motor vehicle, the chain having a plurality of chain links. A plate-link chain of that type is described in the German published application DE 100 47 979 A1. The construction and function of a chain-driven conical-pulley transmission are suggested in that same published unexamined application. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0021]    Additional advantages, features, and details of the invention can be seen from the following description, in which various exemplary embodiments are described in detail with reference to the drawings. The figures show the following: 
           [0022]      FIG. 1  shows a top view of a portion of a plate-link chain in double configuration; 
           [0023]      FIG. 2A  shows a portion of a plate-link chain in a side view in double/triple configuration; 
           [0024]      FIG. 2B  shows a portion of a plate-link chain in a top view in double/triple configuration; 
           [0025]      FIG. 3  shows various embodiments of spacing and/or biasing elements in a side view; 
           [0026]      FIG. 4  shows a perspective view of one of the spacing and/or biasing elements shown in  FIG. 3 ; and 
           [0027]      FIG. 5  shows a top view of a portion of a plate-link chain in triple configuration. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0028]      FIG. 1  shows a plate-link chain portion  1  in double configuration in simplified form. The plate-link portion  1  includes four rocker pressure member pairs  4 ,  5 ,  6 , and  7 . Each rocker pressure member pair  4  through  7  includes two rocker pressure members  8 ,  9 . Two of the rocker pressure member pairs  4  through  7  serve to constitute a chain link  11 ,  12 ,  13 . 
         [0029]    In the double configuration shown in  FIG. 1 , the chain links  11  and  13  are designed as shorter or short chain links. Chain link  12  is designed as a longer or long chain link. The longer chain link  12  includes four plate-links  21  through  24 , which are coupled with one another by the rocker pressure member pairs  5  and  6 . The plate-links  21  through  24  of the long chain link  12  are of identical design. 
         [0030]    The short chain link  11  includes four plate-links  31  through  34 , which are coupled with one another by the rocker pressure member pairs  4  and  5 . The short chain link  13  includes four plate-links  35  through  38 , which are coupled with one another by the rocker pressure member pairs  6  and  7 . The plate-links  31  through  38  of the short chain links  11  and  13  are of identical design. 
         [0031]    A chain running direction extends in the vertical direction in  FIG. 1 . In the plate-link chain portion  1 , the two plate-links  22 ,  23  of the long chain link  12  are disposed medially. The plate-links  31 ,  32 ,  33 ,  34 ,  35 ,  36 ,  37 ,  38  of the short chain links  11  and  13  are combined in pairs. The plate-link pairs  31 ,  32  and  35 ,  36  of the short chain links  11  and  13  contact one another at their longitudinal ends that face one another. 
         [0032]    The plate-link pairs  31 ,  32  and  35 ,  36  are disposed laterally relative to the chain running direction between the plate-links  21  and  22  of the long chain link  12 . The plate-link pairs  33 ,  34  and  37 ,  38  of the short chain links  11  and  13  are similarly disposed laterally relative to the chain running direction between the plate-links  23  and  24  of the long chain link  12 . The longitudinal ends of the plate-link pairs  33 ,  34  and  37 ,  38  that face one another contact one another. 
         [0033]    Intermediate spaces  29 ,  30  are produced between the outer plate-links  21 ,  24  of the long chain link  12  and the plate-links  31 ,  35 ,  34 ,  38  of the shorter chain links  11  and  13  in the arrangement shown in  FIG. 1 . Furthermore, the double configuration in  FIG. 1  includes intermediate spaces  39 ,  40  between the longer plate-links  22 ,  23  of the long chain link  12  and the shorter plate-links  32 ,  36 ,  33 ,  37  of the shorter chain links  11  and  13 . 
         [0034]    The intermediate spaces  29 ,  30  and/or  39 ,  40  are advantageously provided with spacing and/or biasing elements (not shown in  FIG. 1 ). Filling the intermediate spaces  29 ,  30 ,  39 ,  40  fulfills at least one of the following functional options. 
         [0035]    1. weight balancing for a uniform distribution of weight in the plate-link chain; 
         [0036]    2. joint damping by means of elastic elements which lie pre-stressed around the rocker joints; 
         [0037]    3. damping through axial bracing of the plate-links against one another; 
         [0038]    4. springing/damping of the plate-links against the respective neighbor rocker pressure piece in the chain running direction; 
         [0039]    5. springing/damping of the plate-links against following plate-links in the chain running direction. 
         [0040]      FIG. 2A  shows a top view of a portion of a plate-link chain  41  having a long chain link  42 . Within a longer plate-link  43  of the long chain-link  42  there are visible two longitudinal ends or bows  44 ,  45  of plate-links of a longer and a shorter chain link. To the left thereof the same is shown, but in the foreground. 
         [0041]    The mutually facing longitudinal ends or bows  44 ,  45  of the plate-links of the two chain links contact one another. The ends  44 ,  45  are shaped on top so that the plate-links to which they belong are in contact when the chain is in a straight strand, as shown in  FIG. 2A . By straight contacting surfaces at the ends  44 ,  45  or bows in a contact region  48 , unwanted swing-back of the plate-link chain  41  is prevented when it is in the straight strand orientation. 
         [0042]    In the intermediate spaces  29 ,  30  shown in  FIG. 1 , and laterally relative to the chain running direction, between individual plate-links of the longer and shorter chain links spacing and/or biasing elements  51  through  54  are positioned as shown in  FIG. 2B . The spacing and/or biasing elements  51  through  54  on the one hand prevent unwanted telescoping of the longer chain links. In addition, so-called guide tips, which are also referred to as overlap tips and will be explained below in reference to  FIG. 5 , can be eliminated. 
         [0043]      FIG. 3  shows three different forms of spacing and/or biasing elements  61  through  64  in side views. The spacing and/or biasing elements  61 ,  62  and  64  are essentially H-shaped. The spacing and/or biasing element  63  is essentially X-shaped. 
         [0044]    The spacing and/or biasing element  62  has a notch  65  on top. The spacing and/or biasing element  63  has notches  66 ,  67  on top and bottom. The spacing and/or biasing element  64  has a central opening  68 . 
         [0045]      FIG. 4  shows a spacing and/or biasing element  61  of  FIG. 3  in a perspective view. In that view it can be seen that the spacing and/or biasing element  61  is made of a corrugated material having corrugations  69  that extend between opposed longitudinal outer edges of the biasing element  61 . The material from which biasing element  61  is made can be a spring material. 
         [0046]      FIG. 5  shows a plate-link chain portion  71  in triple configuration, also referred to as a triple grouping. The illustrated plate-link chain section  71  includes four rocker pressure member pairs  74  through  77 , which serve to connect three chain links  81  through  83 . The chain links  81  and  83  are designed as shorter chain links. Chain link  82  is designed as a longer chain link. 
         [0047]    The shorter chain link  81  includes four plate-links  31  through  34 , which are designed and identified exactly like the plate-links of the shorter chain link  11  in  FIG. 1 . The longer chain link  82  includes four plate-links  21  through  24 , which are configured and arranged exactly like the plate-links of the longer chain link  12  in  FIG. 1 . 
         [0048]    The shorter chain link  83  includes four plate-links  85 ,  86 ,  87 , and  88 , which are distributed differently than the other plate-links in the plate-link chain portion  71 . At the longitudinal ends of the plate-links  85  through  88  as shown in  FIG. 5 , in an overlap region  90 , there result overlap ends, which are also referred to as guide ends. 
         [0049]    In a manner similar to the previously described spacing and/or biasing elements, the overlap ends prevent unwanted sliding between one another of laterally spaced plate-links of the chain links  81  through  83 . However, the overlap ends or guide ends do not perform a biasing function, as do the spacing and/or biasing elements  61 .