Motion transmission system of a bicycle

Abstract

A bicycle rear wheel sprocket assembly has twelve sprockets in a twelve sprocket assembly. The twelve sprocket assembly is configured to be mounted to a bicycle freewheel hub. The freewheel hub rotates about a rotation axis and has a spoke attachment portion and a frame fastening portion which are spaced apart by an axial distance. End sprockets of the twelve sprocket assembly are positioned within the axial distance.

What is claimed is: 
     
         1 . A bicycle rear wheel sprocket assembly comprising, twelve sprockets in a twelve sprocket assembly configured for mounting to a bicycle freewheel hub, wherein the freewheel hub rotates about a rotation axis and has a spoke attachment portion and a frame fastening portion which are spaced apart by an axial distance, and wherein end sprockets of the twelve sprocket assembly are positioned within the axial distance. 
     
     
         2 . The bicycle rear wheel sprocket assembly of  claim 1 , wherein the sprocket assembly is bounded by a first plane positioned at the spoke attachment portion and a second plane positioned at the frame fastening portion. 
     
     
         3 . The bicycle rear wheel sprocket assembly of  claim 2 , wherein a maximum axial width of the sprocket assembly is no greater than 46 mm. 
     
     
         4 . The bicycle rear wheel sprocket assembly of  claim 2 , wherein a maximum axial width of the sprocket assembly is no greater than 43.5 mm. 
     
     
         5 . The bicycle rear wheel sprocket assembly of  claim 2 , wherein a first end sprocket of the twelve sprocket assembly is immediately adjacent to the first plane and a second end sprocket of the twelve sprocket assembly opposite to the first end sprocket is immediately adjacent to the second plane. 
     
     
         6 . The bicycle rear wheel sprocket assembly of  claim 1 , wherein each sprocket is generally planar in the area of the rotation axis. 
     
     
         7 . The bicycle rear wheel sprocket assembly of  claim 1 , wherein inner diameter surfaces of all of the twelve sprockets are parallel to the rotation axis. 
     
     
         8 . The bicycle rear wheel sprocket assembly of  claim 1 , wherein a distance measured between respective outer faces of end sprockets in the assembly is no greater than 42.5 mm. 
     
     
         9 . The bicycle rear wheel sprocket assembly of  claim 8 , wherein a distance measured between respective outer faces of end sprockets in the assembly is no greater than 40.5 mm. 
     
     
         10 . A bicycle motion transmission system, comprising:
 a freewheel body of a rear wheel hub having a first plane that is perpendicular to a rotation axis of the rear wheel hub and is defined by an axially inner most portion of the hub that includes spoke attachment seats, and a second plane that is perpendicular to the rotation axis of the rear wheel hub, and is defined by a portion of the hub that includes a frame attachment portion; and   twelve sprockets that define a twelve sprocket assembly mounted on the freewheel body of the rear wheel hub with a first end sprocket and second end sprocket that are the outermost sprockets of the twelve sprocket assembly, and the first end sprocket and the second end sprocket are bounded by the first and second planes.   
     
     
         11 . The bicycle motion transmission system of  claim 10  wherein a maximum axial width of the sprocket assembly is no greater than 46 mm. 
     
     
         12 . The bicycle motion transmission system of  claim 10 , wherein a maximum axial width of the sprocket assembly is no greater than 43.5 mm. 
     
     
         13 . The bicycle motion transmission system of  claim 10 , wherein the first end sprocket is immediately adjacent to the first plane and the second end sprocket is immediately adjacent to the second plane. 
     
     
         14 . The bicycle motion transmission system of  claim 10 , wherein the first end sprocket is spaced inwardly from the first plane in a direction toward a center of the twelve sprocket assembly and the second end sprocket is spaced inwardly from the second plane in a direction toward a center of the twelve sprocket assembly. 
     
     
         15 . The bicycle motion transmission system of  claim 10  further including a chain having an alternating succession of outer links comprised of two parallel plates and inner links comprised of two parallel plates, the outer and inner links are connected to each other at respective connection and are spaced apart to define a sprocket tooth receiving space between the two parallel inner plate. 
     
     
         16 . The bicycle motion transmission system of  claim 10 , wherein a distance measured between respective outer faces of end sprockets in the assembly is no greater than 42.5 mm. 
     
     
         17 . The bicycle motion transmission system of  claim 16 , wherein a distance measured between respective outer faces of end sprockets in the assembly is no greater than 40.5 mm. 
     
     
         18 . A combination of a bicycle rear wheel sprocket assembly and a drive chain, comprising:
 a twelve sprocket assembly with first and second end sprockets being the outermost sprockets of the twelve sprocket assembly, the first and second end sprockets both being bounded by a first plane that is perpendicular to a rotation axis of a rear wheel hub, and is defined by an axially inner most portion of the hub that includes spoke attachment seats, and a second plane that is perpendicular to the rotation axis of the rear wheel hub, and is defined by a portion of the hub that includes a frame attachment portion; and   a chain having an alternating succession of outer links comprised of two parallel plates and inner links comprised of two parallel plates, the outer and inner links are connected to each other at respective connection and are spaced apart to define a sprocket tooth receiving space between the two parallel inner plates.   
     
     
         19 . The combination of  claim 18 , wherein the chain has a maximum thickness, as measured at the parallel outer links, between and including 4.6 mm and 5.8 mm. 
     
     
         20 . The combination of  claim 19 , wherein the chain has a maximum thickness which is greater than 4.8 mm. 
     
     
         21 . The combination of  claim 20 , wherein the chain has a maximum thickness which is greater than 5.0 mm. 
     
     
         22 . The combination of  claim 18 , wherein a maximum axial width of the sprocket assembly is no greater than 46 mm. 
     
     
         23 . The combination of  claim 22 , wherein a maximum axial width of the sprocket assembly is no greater than 43.5 mm. 
     
     
         24 . The combination of  claim 18 , wherein the first end sprocket is immediately next the first plane and the second end sprocket is immediately next the second plane. 
     
     
         25 . The combination of  claim 18 , wherein a distance measured between respective outer faces of end sprockets in the assembly is no greater than 42.5 mm. 
     
     
         26 . The combination of  claim 25 , wherein a distance measured between respective outer faces of end sprockets in the assembly is no greater than 40.5 mm. 
     
     
         27 . A bicycle rear wheel sprocket assembly comprising, twelve sprockets in a mounting assembly configured for mounting to a bicycle freewheel hub that rotates about a rotation axis, the bicycle freewheel hub has a spoke attachment portion and a frame fastening portion that are axially separated to define between them an axial mounting space where the mounting assembly with the twelve sprockets mounts to the bicycle freewheel hub with extreme end sprockets of the twelve sprockets positioned perpendicular to the rotation axis and within the mounting space. 
     
     
         28 . A bicycle motion transmission system, comprising:
 a bicycle rear wheel sprocket assembly comprising twelve sprockets in a twelve sprocket assembly configured for mounting to a bicycle free wheel hub, the twelve sprockets including a largest sprocket and a smallest sprocket; and   a chain configured to engage sprocket teeth of each of the twelve sprockets, wherein:
 the freewheel hub has a spoke attachment portion and a frame fastening portion which are spaced apart by an axial distance;
 the chain is comprised of alternating inner and outer links that are connected to each other, each inner and outer link includes two spaced apart plates that define a void that receives one tooth of at least one of the sprockets; and 
 the chain remains within the axial distance when it moves over the sprocket assembly from the smallest sprocket to the largest sprocket. 
 
   
     
     
         29 . The bicycle motion transmission system of  claim 28 , wherein the twelve sprockets in a twelve sprocket assembly are mounted within the predetermined axial distance.