MECHANICAL CONVERSION DEVICE OF THE DOUBLE-CRANK TYPE WITH VARIABLE ANGULAR OFFSET OF THE CRANKS, AND CRANK GEAR OBTAINED WITH SUCH DEVICE

摘要

The invention relates to a mechanical conversion device of the double crank type, capable of generating a continuous rotation motion under the effect of efforts applied alternatively to both cranks. According to the invention, the power torques exerted alternatively on both cranks are applied on two coaxial rotary shaft sections (1, 2) synchronized by means of a transmission system (10, 11, 12, 13) capable of generating an angular offset between said two sections (1, 2), such angular offset varying as a function of the position of the section (1, 2) to which is applied a power torque. The invention applies particularly to the fabrication of a bicycle crank gear.