Analytical flat belt drive model considering bilinear elastic behaviour with residual strains

Abstract

In this work an analytical model of a steady-state flat belt drive with multiple driving and driven pulleys is presented. The belt is characterised by a novel bilinear elastic constitutive description with a superposition of residual strain due to viscoelastic effects, such as relaxation, and considering inertia effects. Both prevalent tensioning methods for the drive are examined: the pretensioning of the belt to a target pre-strain, and the utilization of a tension pulley to ensure adequate tension in the drive.The model is discussed based on a case study. The enhanced accuracy in modelling the mechanical response of the belt results in more accurate estimation of the maximal transmissible power as well as the state of tensile strain of the belt. Traditionally, the maximal transmissible power and tensile strain of the belt are overestimated. Consequently, the potential for failures arising from drives operating proximate to their operational thresholds can be effectively mitigated. The more accurate description of the belt state can lead to better utilization of the belt capabilities and a larger design space when dimensioning the belt drive.Furthermore, the advantages of employing a tension pulley for belt drive tensioning are demonstrated under the assumed conditions.