One of the most important factors in a belt-driven system is tension acting on the belt because it significantly affects the life of belt as well as the efficiency and quality of power transmission. The tension in the flexible belt consists of both static and dynamic components, which should contain all the information on the state of power transmission. The static component corresponds to the steady state power transmission while noncircularity or eccentricity of the pulley system, surface irregularity of belt and pulley, dynamic loading etc. are responsible for the dynamic component. For quality control of the belt-driven systems only static tension has so far been used as a guide. But, as the dynamic component contains useful information on the total system as mentioned above, it would be very beneficial for quality control and diagnosis of the overall system to have a handy tool which can provide both static and dynamic components of tension.
A method of identifying both components of tension under operating conditions is introduced in this work. The method is based on the analysis of the transverse vibrations of an axially moving belt under the condition of time varying tension. Frequency characteristics of transient vibrations of the belt caused by an impact on it are analysed and related to the static and dynamic components of the tension. An appropriate parameter representing the overall quality of the belt driving systems is proposed. The method is confirmed by comparing the tension identified by the proposed procedure with the actual measurements of the tension.