Continuously variable transmission

Abstract

Traction planets and traction rings can be operationally coupled to a planetary gearset to provide a continuously variable transmission (CVT). The CVT can be used in a bicycle. In one embodiment, the CVT is mounted on the frame of the bicycle at a location forward of the rear wheel hub of the bicycle. In one embodiment, the CVT is mounted on and supported by members of the bicycle frame such that the CVT is coaxial with the crankshaft of the bicycle. The crankshaft is configured to drive elements of the planetary gearset, which are configured to operationally drive the traction rings and the traction planets. Inventive component and subassemblies for such a CVT are disclosed. A shifting mechanism includes a plurality of pivot arms arranged to pivot about the centers of the traction planets as a shift pin hub moves axially.

1 .- 14 . (canceled)  
   
   
       15 . A bicycle comprising: 
 a crankshaft;    a rotatable planetary gear set carrier coupled to the crankshaft;    a plurality of planet gears coupled to said carrier;    a ring gear, rotationally constrained, coupled to the planet gears;    a sun gear coupled to the planet gears;    a first traction ring operationally coupled to the sun gear;    a plurality of traction planets coupled to the traction ring; and    a second traction ring coupled to the traction planets.    
   
   
       16 . The bicycle of  claim 15 , further comprising a cage coupled to the crankshaft and adapted to transfer power to the traction planets.  
   
   
       17 . The bicycle of  claim 16 , wherein the traction planets are spherical rollers.  
   
   
       18 . The bicycle of  claim 15 , further comprising an axial force reaction sleeve.  
   
   
       19 . The bicycle of  claim 15 , further comprising an axial thrust bearing.  
   
   
       20 . The bicycle of  claim 15 , further comprising a traction sun.  
   
   
       21 . The bicycle of  claim 15 , further comprising at least one load cam assembly.  
   
   
       22 . The bicycle of  claim 21 , wherein the load cam assembly comprises load cam rollers and ramps.  
   
   
       23 . A bicycle comprising: 
 a crankshaft;    a rotatable planetary gear set carrier coupled to the crankshaft;    a plurality of planet gears coupled to said carrier;    a ring gear, rotationally constrained, coupled to the planet gears;    a sun gear coupled to the planet gears;    a first traction ring operationally coupled to the sun gear and coaxially mounted about the crankshaft;    a plurality of traction planets coupled to the traction ring; and    a second traction ring coupled to the traction planets and coaxially mounted about the crankshaft.    
   
   
       24 . The bicycle of  claim 23 , further comprising a cage rigidly coupled to members of the frame of the bicycle, the cage configured to support the plurality of traction planets axially and radially.  
   
   
       25 . The bicycle of  claim 23 , further comprising a housing that is integral with the frame members of the bicycle.  
   
   
       26 . A bicycle transmission comprising: 
 a planetary gear set configured for coupling to a crankshaft of a bicycle and to be mounted coaxially about said crankshaft; and    a continuously variable variator coupled to said planetary gearset configured to be mounted coaxially about said crankshaft.    
   
   
       27 . The bicycle transmission of  claim 26 , wherein the transmission is configured to be mounted on frame members of the bicycle.  
   
   
       28 . The bicycle transmission of  claim 27 , wherein the transmission is mounted forward of the rear wheel.  
   
   
       29 . The bicycle transmission of  claim 28 , wherein the transmission is mounted on the bottom bracket of the bicycle.  
   
   
       30 . The bicycle transmission of  claim 26 , wherein the crankshaft is coupled to a carrier of the planetary gearset.  
   
   
       31 . The bicycle transmission of  claim 26 , wherein the crankshaft is coupled to a ring gear of the planetary gearset.  
   
   
       32 . The bicycle transmission of  claim 26 , wherein the ring gear of the planetary gearset is constrained rotationally.  
   
   
       33 . The bicycle transmission of  claim 26 , wherein the crankshaft is coupled to a cage of the variator.  
   
   
       34 . The bicycle transmission of  claim 26 , wherein a sun gear of the planetary gearset is coupled to an input driver of the variator.  
   
   
       35 . The bicycle transmission of  claim 26 , wherein a carrier of the planetary gearset is constrained rotationally.  
   
   
       36 . The bicycle transmission of  claim 26 , wherein a cage of the variator is rigidly coupled to the frame members of the bicycle.  
   
   
       37 - 50 . (canceled)