Abstract:
A torque converter including a turbine, an output shaft, and a damper having at least one cover plate radially fixed to the turbine, a flange driven by the damper and non-rotatably connected to the output shaft, the flange having an axially extending surface centering the cover plate.

Description:
[0001]    Priority to U.S. Provisional Application Ser. No. 60/964,855, filed Aug. 15, 2007, German Patent Application No. 10 2006 056 299.2, filed Nov. 29, 2006, U.S. Provisional Patent Application Ser. No. 60/874,104, filed Dec. 11, 2006, German Patent Application No. 10 2006 061 541.7, filed Dec. 27, 2006, German Patent Application No. 10 2006 061 553.0, filed Dec. 27, 2006, German Patent Application No. 10 2006 061 552.2, filed Dec. 27, 2006, U.S. Provisional Patent Application Ser. No. 60/934,235, filed Jun. 12, 2007, and U.S. Provisional Patent Application Ser. No. 60/962,772, filed Jul. 31, 2007, is claimed. 
     
    
       [0002]    The present invention relates generally to hydraulic torque converters, and more particularly to hydraulic torque converters with lock-up clutches and dampers. 
       BACKGROUND OF THE INVENTION 
       [0003]    In  FIG. 1 , a prior art torque converter  10  contains a cover  12 , an impeller  14 , a turbine  16 , a stator  18 , a lock-up clutch  20 , and a damper  22 . Torque converter  10  is driven by an engine connected with studs  24 ,  26 . Impeller  14  is rigidly attached to cover  12 . Turbine  16  is rigidly attached to a turbine hub  28  with, for example, rivets  30 . Turbine hub  28  is non-rotatably attached to an output shaft  32  with, for example, splines  34 . Turbine hub  28  centers turbine  16  around output shaft  32 . 
         [0004]    A piston  36  and a piston hub  38  of lock-up clutch  20  may move axially on an outer hub  40  of turbine hub  28  according to the controlled pressure difference between regions  42 ,  44  on either axial side of piston  36 . When piston  36  is not contacting cover  12  at a surface  46 , torque is transferred from the engine to output shaft  32  through the hydraulic fluid in torque converter  10 . When piston  36  is contacting cover  12  at surface  46 , torque is transferred from the engine to output shaft  32  through springs  48  in damper  22 . U.S. Pat. No. 5,385,222 is hereby incorporated by reference herein. 
       SUMMARY OF THE INVENTION 
       [0005]    The present invention provides a torque converter comprising a turbine, an output shaft, and a damper having at least one cover plate radially fixed to the turbine, and a flange driven by the damper and non-rotatably connected to the output shaft, the flange having an axially extending surface centering the cover plate. 
         [0006]    The present invention advantageously permits the turbine to be centered using the flange. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]      FIG. 1  shows a prior art torque converter; 
           [0008]    One embodiment of the present invention is shown with respect to the drawings in which: 
           [0009]      FIG. 2  shows one embodiment of a torque converter according to the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0010]      FIG. 2  describes a torque converter  110  according to the present invention, having a cover  112 , an impeller  114 , a turbine  116 , a stator  118 , a lock-up clutch  120 , and a damper  122 . Impeller  114  is rigidly attached to cover  112 . Turbine  116  is rigidly attached to cover plate  150  with, for example, rivets  154 . Stator  118  is mounted on a one-way clutch  156  with an outer race  158  and an inner race  160  non-rotatably attached to a stator shaft  162  with, for example, splines  164 . 
         [0011]    Lock-up clutch  120  includes a piston  136 , a clutch plate  166 , and cover plates  150 ,  152 . Cover plates  150 ,  152  are non-rotatably connected to clutch plate  166  with, for example, splines  168 . Piston  136  may move axially on a cover flange  170  according to a controlled pressure difference between regions  172 ,  174  on either axial side of piston  136 . Lock-up clutch  120  is open when piston  136  is positioned axially towards the turbine  116 . Lock-up clutch  120  is closed when piston  136  is positioned axially towards engine to engage friction surfaces  176 ,  178 ,  180 ,  182  on clutch plate  166 , cover  112 , and piston  136 . 
         [0012]    Damper  122  includes cover plates  150 ,  152  retaining an annular arrangement of springs  184 . Springs  184  contact a flange  186  non-rotatably connected to an output shaft  188  with, for example, splines  190 . Output shaft  188  can be the input shaft of a transmission, for example. 
         [0013]    Cover flange  170  is attached rigidly to cover  112 . Adjacent to cover flange  170  are seals  192 ,  194  to seal output shaft  188  and piston  136 . Cover  112  is centered in an engine crankshaft with a cover pilot  195  extended from cover  112 . Cover flange  170  is centered by cover  112 . Flange  186  is centered in cover flange  170  with a bearing  206 . Cover plate  150  and turbine  116  are centered on flange  186  at an axially extending surface  196 . Output shaft  188  is centered in flange  186 . A thrust bearing  198  is centered in turbine  116  at a tubular surface  200 . 
         [0014]    Engine torque enters the torque converter  110  through a stud  202 . Torque from stud  202  is transmitted to cover  112 . Torque from cover  112  can be transmitted to either impeller  114  or clutch plate  166 , depending on whether lock-up clutch  120  is open or closed. 
         [0015]    When lock-up clutch  120  is open, torque from cover  112  is transmitted to impeller  114 . Impeller  114  transmits torque to turbine  116  through the oil in torque converter  110 . Turbine  116  transmits torque to cover plate  150 . Cover plate  150  transmits torque into flange  186  through springs  184 . If the torque exceeds the capacity of springs  184 , flange  186  will directly contact cover plate  150  at area  204 . Flange  186  directly transmits torque into output shaft  188 . Flange  186  transmits axial thrust from turbine  116  to bearing  206  supported on cover flange  192 . Flange  186  has a U-shaped section with one leg having axially extending surface  196  and the other having splines for interacting with splines  190 . 
         [0016]    When lock-up clutch  120  is closed, torque from cover  112  is transmitted to clutch plate  166 . Clutch plate  166  transmits torque into cover plate  150 . Cover plate  150  has additional inertia of turbine  116 . Cover plate  150  transmits torque into flange  186  through springs  184 . If torque exceeds the capacity of springs  184 , flange  186  will directly contact cover plate  150  at area  204 . Flange  186  directly transmits torque into output shaft  188 . 
         [0017]    By mounting flange  186  on output shaft  188  and contacting flange  186  to springs  184  in damper  122 , the use of hubs  38 ,  40  in the prior art shown in  FIG. 1  is advantageously avoided without adding additional pieces. Providing flange  186  with axially extending surface  196  advantageously centers cover plate  150  and turbine  116  on flange  186  and centers output shaft  188 . Design of the torque converter is thus simplified and cost is reduced.