Abstract:
A torque coupler includes an input side and an output side, which are situated rotatably around an axis of rotation, and in addition an intermediate plate for coupling with the input side, an output flange for coupling with the output side, a spring damper for coupling the intermediate plate with the output flange, and a centrifugal force pendulum having a pendulum flange and a pendulum mass. Here the pendulum flange extends between a first area, in which the pendulum flange is attached to the intermediate plate, and a second area, in which the pendulum mass is attached to the pendulum flange. The output flange has a cutout, through which a section of the pendulum flange which connects the two areas runs.

Description:
The invention relates to a torque coupler, in particular for use in a drivetrain of a motor vehicle. 
     BACKGROUND 
     A torque coupler is used to transmit torque in a drivetrain of a motor vehicle. On the one hand, the torque coupler provides a torsional connection of an output shaft of a drive motor to a drive shaft of a transmission, and, on the other hand, it is set up to damp or cancel out torsional vibrations that are superimposed on the transmitted torque. To that end, the torque coupler includes a spring damper and a centrifugal force pendulum. The spring damper includes an elastic element whose ends are connected to an input side or an output side of the torque coupler, in order to compress or to decompress the spring damper under the influence of a changing torque. The centrifugal force pendulum includes a pendulum flange, on which a pendulum mass is movably situated in the plane of rotation, so that the pendulum mass is moved radially inward or outward under the influence of the angular acceleration, thus reducing or cancelling out the torsional vibration which is the basis of the angular acceleration. 
     A flange or a disk which transmits the torque from the input side to the spring damper is usually fastened to the pendulum flange by means of a spacer bolt. The spacer bolt is necessary in order to leave an axial intermediate space between the pendulum flange and the other flange or the disk, in which space an output flange for coupling with the output side is located. The spacer bolt is riveted to both flanges during the assembly of the torque coupler. In this design it is disadvantageous that the spacer bolt or riveted connection is not subjected merely to shear during operation of the torque coupler, but that in addition a bending force is also operative, which may reduce the service life of the connection. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to provide a torque coupler having an improved connection of the pendulum flange to the other flange. 
     A torque coupler according to the present invention includes an input side and an output side, which are situated rotatably around an axis of rotation, and in addition an intermediate plate for coupling with the input side, an output flange for coupling with the output side, a spring damper for coupling the intermediate plate with the output flange, and a centrifugal force pendulum having a pendulum flange and a pendulum mass. Here the pendulum flange extends between a first area, in which the pendulum flange is attached to the intermediate plate, and a second area, in which the pendulum mass is attached to the pendulum flange. The output flange has a cutout, through which a section of the pendulum flange which connects the two areas runs. 
     By this means, the pendulum flange can be brought closer to the intermediate plate in the first area, so that a connection, in particular a rivet or bolt connection may be employed with reduced axial leverage. A bending load can be reduced thereby, whereby the life of the connection can be increased. Because of the reduced loading, the connection can also be dimensioned more weakly, which may result in cost benefits, and additional construction space can be gained in the area of the connection. 
     The pendulum flange is preferably in direct contact with the intermediate plate in the area where it is attached. The attachment of the pendulum flange to the intermediate plate can thus take place completely in cohesive friction, so that a bending loading of a connecting element does not occur. By reducing effective leverage of the fastening element to zero, the fastening element can be subjected exclusively in the axial direction to tension, or possibly also to shear, but not to bending. This achieves a greater strength of the connection. 
     In an especially preferred embodiment, the cutout is dimensioned so that the section of the pendulum flange which passes through it runs against a boundary of the cutout once a predetermined maximum torsional angle between the intermediate plate and the output flange is reached. The torsional angle correlates with a working stroke of the spring damper. By the striking of the pendulum flange on the boundary of the cutout a stop is formed, which is able to limit the working stroke of an elastic element of the spring damper, and thus to protect the element from overloading. A stop in the area of the elastic element can thus be saved. This makes it possible to gain construction space in the area of the spring damper. Furthermore, through the multiple use of the pendulum flange for different tasks, the torque coupler can be designed more compactly. 
     In one embodiment, the intermediate plate includes two plate elements that are offset axially and connected to each other, which lie on different axial sides of the output flange, while the pendulum flange is attached to the plate element which faces away from it. A radial length of the plate element which faces toward the pendulum flange can be reduced thereby. This construction suggests itself in particular for an axially cranked output flange. 
     The cutout may extend in a section of the output flange that runs purely radially, and in a section connected thereto which also runs radially. The strength of the output flange can be reduced only slightly by such a cutout. 
     The pendulum flange may be cranked, and the cranked zone may run through the cutout. In particular, the pendulum flange and the output flange may be cranked in different axial directions. The pendulum flange can be connected thereby to the output flange in an optimal manner, in order to achieve a compact and frictional arrangement of the elements of the torque coupler. 
     In a further preferred embodiment, the torque coupler also includes an additional spring damper to couple the input side with the intermediate plate, the two spring dampers being radially offset and concentrically arranged. The pendulum mass attached to the pendulum flange can thereby be axially closely adjacent to the two spring dampers, in order to make optimal use of an available construction space. 
     In yet another embodiment, the torque coupler may also include a turbine, the turbine and the pendulum flange being attached to the intermediate plate by means of a common connecting element. The common connecting element may be designed in particular as a rivet or bolt, and, as explained earlier, may be subjected to tension or to tension and shear, but not to bending. The integrated attachment of the turbine and of the pendulum flange to the intermediate plate may thus have an increased loading capacity. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will now be described in greater detail by reference to the accompanying figures, in which the figures represent the following: 
         FIG. 1  a sectional view of a torque coupler; 
         FIG. 2  a sectional view of an expanded torque coupler, based on the torque coupler from  FIG. 1 ; 
         FIG. 3  an oblique view of the torque coupler from  FIG. 2 ; 
         FIG. 4  a sectional view of the torque coupler from  FIG. 1  in a different rotational position than in  FIG. 2 ; and 
         FIG. 5  an oblique view of the torque coupler from  FIG. 4 . 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  shows a sectional view of a torque coupler  100 . The depiction shows only the upper half of a longitudinal section through an axis of rotation  105 , around which the elements of the torque coupler  100  are rotatably positioned. 
     The depicted torque coupler  100  includes a retainer  110  for connecting to an input side to introduce a torque, a first elastic element  115 , a first (here left-side) plate element  120  and a second (here right-side) plate element  120 , the plate elements  120  and  125  being enclosed by an intermediate plate  130 ; also a second elastic element  135 , an output flange  140 , a hub  145 , a connecting element  150 , a turbine  155  merely suggested in  FIG. 1 , as well as a centrifugal force pendulum  160 , which includes a pendulum flange  165  and a pendulum mass  170 . 
     Not all of the named components of the torque coupler  100  are absolutely necessary. The focal point of the present invention is the attachment of the pendulum flange  165  to the intermediate plate  130 . The remaining elements may also be omitted from different embodiments of the torque coupler  100 , or additional elements may be included. 
     The elastic elements  115  and  135  may be designed as compression springs or as bow springs. At the same time, each of the elastic elements  115  and  135  may be made up of a plurality of individual elastic elements, which are connected to each other in series or in parallel. In a preferred embodiment, at least the first elastic element  115  includes a bow spring. The retainer  110  serves to link torque from the input side to an end of the first elastic element  115 , and at the same time to brace the first elastic element  115  radially or axially. An opposite end of the first elastic element  115  is engaged with the intermediate plate  130 . By preference, the engagement occurs through a contact of the second end with a section of one of the plate elements  120  or  125  provided for that purpose. 
     The plate elements  120  and  125  are rigidly joined with each other, for example by means of a riveted connection. In the axial direction between the plate elements  120  and  125  is a section of the output flange  140 . The plate elements  120  and  125 , similarly to the retainer  110 , are set up to brace the second elastic element  135  in a radial or axial direction and to be engaged with one end of the second elastic element  135 , in order to transmit a force. The second end of the second elastic element  135  is engaged with a section of the output flange  140 , in order to exchange forces with the latter. 
     The output flange  140  may be connected to the hub  145  in a single piece or in multiple pieces. In a different embodiment, a decoupling of the torque transmitted from the output flange  140  by the torque coupler  100  occurs in a different way than by means of the hub  145 . 
     The pendulum flange  165  is preferably cranked in the axial direction, so that it appears S-shaped in the depicted sectional view. On the pendulum flange  165  there are a radially inner area  175  and a radially outer area  180 , between which a middle section  185  is located. In the radially inner area  175  the pendulum flange  165  is connected by means of the connecting element  150  to the intermediate plate  130 , in particular to that plate element  125  which lies on the distant axial side of the pendulum flange  165 . For the connection, the pendulum flange  165  preferably lies in direct contact with the plate element  125  in the radially inner area  175 . The connecting element  150  comprises, for example, a bolt or a rivet. In one embodiment, the connecting element  150  also attaches the turbine  155  to the intermediate plate  130 . Preferably, the connecting element  150  extends in the axial direction, while the pendulum flange  165 , the intermediate plate  130  and possibly the turbine  155  preferably extend in the connecting area in a purely radial direction. 
     The middle section  185  of the pendulum flange  165  runs through a cutout  190 , which is introduced into the output flange  140 . In a preferred embodiment, the output flange  140  is also cranked in the axial direction, with the cranking running in the opposite direction to that of the pendulum flange  165 , so that sections of the pendulum flange  165  and of the output flange  140  intercross in an X-pattern. 
     The cutout  190  may take different axial positions relative to the cranking of the output flange  140 . In the depicted, preferred embodiment the cutout  190  covers a purely radially running section, and a section of the output flange  140  that is connected thereto and also runs radially. In the depicted, preferred embodiment, an axial section of the radially inner area  175  of the pendulum flange  165  still lies inside the cutout  190  of the output flange  140 . In another embodiment, the lower area  175  can also completely run through the cutout  190  axially. 
       FIG. 2  shows a sectional view of an expanded torque coupler  100 , based on the torque coupler from  FIG. 1 . The torque coupler  100  depicted here includes additional elements, in order to make it easier to understand how the tie-in of the pendulum flange  165  on the output flange  140  is embedded in the torque coupler  100 . It is true here as well that not all depicted or described components of the torque coupler  100  must be used in order to be able to utilize the advantages of the present invention. 
     As additional elements, compared to the embodiment depicted in  FIG. 1 , the depicted torque coupler  100  includes a friction clutch  215  and a piston  220 . In the depicted, preferred embodiment, the input side  210  is depicted as a housing which encloses the rest of the components of the torque coupler  100 . By preference, the torque coupler  100  may run in a fluid bath, in particular an oil bath, which is closed off by the housing. In a radial outer area of the input side  210 , the friction plate  215  rests against the latter. A piston  220  is set up to exert an axial force on the friction plate  215 , in order to press the latter against the input side  210  and so produce a frictional engagement. The friction plate  215  is torsionally engaged with the retainer  110 . 
     It is clear in  FIG. 2  how one end of the first elastic element  115  fits closely with sections of the left plate element  120  in  FIG. 2  and of the retainer  110 . Also clearly recognizable is the axial passage of the middle section  185  of the pendulum flange  165  through the cutout  190  in the output flange  140 , while the output flange  140  in the embodiment of  FIG. 2  is integrated with the hub  145 . 
       FIG. 3  shows an oblique view of the torque coupler  100  from  FIG. 2 . From this perspective it can be seen that in the embodiment shown, different axial connecting elements  150  are used to connect the turbine  155  and the pendulum flange  165  each to the plate element  125  of the intermediate plate  130 . In another embodiment, a combined connecting element  150  may also be used for both attachments. 
     In the perspective shown, a preferred embodiment is recognizable, in which the cutout  190  is dimensioned so that the middle section  185  of the pendulum flange  165  runs against a boundary  305  of the cutout  190  when a predetermined maximum torsional angle between the intermediate plate  130  and the output flange  140  is reached. To that end, the dimensions of the cutout  190  are chosen depending on a width of the middle section  185  of the pendulum flange  165  in the circumferential direction and the magnitude of a maximum torsional angle between the intermediate plate  130  and the output flange  140 . 
     Although only a cutout  190  and a middle section  185  of the pendulum flange  165  that passes through it are depicted, these elements can be repeated on a circumference around the axis of rotation  105 , in order to increase a loading capacity of the connection. 
       FIG. 4  shows a sectional view of the torque coupler  100  from  FIG. 1  in a different rotational position than in  FIG. 2 . In  FIG. 4 , in particular sections of the side plates  120  and  125  and of the output flange  140 , which are set up to be in contact with one end of the second elastic element  135  (not shown), are readily recognizable. 
       FIG. 5  shows an oblique view of the torque coupler  100  from  FIG. 4 . It becomes clear how a plurality of radial appendages is formed on the pendulum flange  165 , which protrude through a corresponding plurality of cutouts  190  in the output flange  140  in the axial direction. The middle sections  185  lie along a circumference around the axis of rotation  105 , each centered in the cutouts  190 , while the second elastic element  135  is in a maximally relaxed position. The second elastic element  135  is compressed against the output flange  140 , both with a positive and with a negative rotation of the intermediate plate  130 , while the middle section  175  is pushed into the cutout  190  of the output flange in the clockwise or the counter-clockwise direction, until it runs against one of the boundaries  305  and thus limits the compression of the second elastic element  135 . 
     REFERENCE LABELS 
     
         
           100  torque coupler 
           105  axis of rotation 
           110  Retainer 
           115  first elastic element 
           120  first plate element 
           125  second plate element 
           130  intermediate plate 
           135  second elastic element 
           140  output flange 
           145  Hub 
           150  connecting element 
           155  Turbine 
           160  centrifugal force pendulum 
           165  pendulum flange 
           170  pendulum mass 
           175  radially inner area of the output flange 
           180  radially outer area of the output flange 
           185  middle section 
           190  Cutout 
           205  friction clutch 
           210  input side 
           215  friction plate 
           220  Piston 
           305  Boundary