Patent ID: 6364798
Filing Date: 2002-04-02
Classification: F16H

Abstract:
A drive system comprising:a roller chain having multiple rollers and articulated links, said rollers being arranged with a substantially constant pitch and connected by said articulated links; and a sprocket in driving or driven engagement with said roller chain, the sprocket comprising: angularly spaced sprocket teeth arranged for driving or driven engagement with said rollers wherein the spacing between at least some of said sprocket teeth is a multiple of the pitch of said rollers such that during each rotation of said sprocket at least some of said rollers pass over said sprocket and have no driving or driven connection with said sprocket; spoked portions extending radially from a sprocket axis corresponding to said sprocket, each of said spoked portions having an outer end for supporting a corresponding one of said sprocket teeth, wherein the spoked portions flex tangentially under load sufficiently to accommodate variations in the distance between adjacent rollers from the average pitch; and a support profile between adjacent ones of said sprocket teeth having an arc with a radius of curvature centered on the sprocket rotational axis, said arc having a radius substantially equal to the root radius of the sprocket teeth, said support profile comprising resilient inserts extending towards the sprocket axis between said spoked portions.