US Patent 6908406 Continuously variable transmission with elastomeric meshing interface

A system for transmitting power from a driving, or input, shaft to a driven, or output, shaft by way of an elastomeric belt nipped between opposing surfaces associated with the driving and driven shafts utilizes opposing surfaces which define a plurality of indentations disposed thereacross. Each indentation of the surfaces includes a cavity for accepting a portion of the elastomeric belt as the belt passes between the opposing surfaces and as edge which borders the cavity at the corresponding surface. As power is transmitted from the driving shaft to the driven shaft, significant shear and normal forces are applied between the edges of the indentations and the portions of the belt accepted by the indentations.