VARIABLE DIAMETER GEAR DEVICE WITH DIAMETER CHANGER FOR CONSTANT PITCH GEAR TOOTH SEQUENCE

摘要

A variable diameter gear device for variable ratio transmission systems has a displaceable gear tooth sequence (11) formed from interconnected gear teeth (12) with uniform pitch lying on a virtual cylinder coaxial with an axle (20) of the device. A torque linkage (24) transfers a turning moment between the axle and the gear tooth sequence. A diameter changer includes at least one disc (14) with a spiral track (16) to which each of the gear teeth is linked. Rotation of the discs relative to the axle causes variation of an effective diameter of the virtual cylinder while the gear tooth sequences remain on a virtual cylinder centered on the axis (22) and the uniform pitch remains constant.