Effects of deformation in the dynamics of belt drive

The dynamics of a belt drive is considered in the framework of a nonlinear model of an extensible elastic string. Under the assumption of contour motion, in which the trajectories of particles of the string are pre-determined, we transform the general equations of string dynamics to the spatial description. Further simplification regarding the absence of slip of the belt on the surface of the pulleys leads to a new model with a discontinuous velocity field and concentrated contact forces. It is shown how the computed parameters of steady operation of the drive are influenced by the chosen strain measure for the string, and differences in the behavior of synchronous and friction belt drives are pointed out. For a sample set-up, we study the dependence of the maximal transmitted moment on the angular velocities of the pulleys and on the pre-tension of the belt.