Static And Dynamic Analysis On The Measurement System Of An Electronic Belt Scale

The electronic belt scale, widely applied in industry, is a type of measurement equipment continuously weighing the material during the process of bulk solid materials transportation by the belt conveyor. It is always, in fact, a hot issue with respect to improve the measurement accuracy in the design and manufacture of the belt scale. In response to the problem mentioned above, this paper, proceeding from dynamics, probes into the dynamic response of the weighing sensor of electronic belt scale, and explores the effective way of enhancing its measurement precision.Focusing on a direct loading electronic belt scale, one mainly discusses the question of statics and dynamics in the process of measurement. Progress and issues in the study of the weight scale are reviewed first, including their features, classification and technology studies. Based on the principle of weighing, the structures of the electronic instrument are illustrated, the strains of measuring points in a weighing sensor are calculated through the employment of ANSYS, as well as the influence of horizontal and vertical forces on the sensor output is discussed. The measuring errors across all situations, of electronic belt scale with a single supporting roller, are analyzed, the probable causes of which also have been discussed, meanwhile proposing the method of decreasing errors.Secondly, the differential equations of motion for coupled vibration over the entire weighing area, based on the dynamic analysis over this area, have been constructed, which can be settled with the method of Runge-Kutta, the results revealing the change in forces exerted upon the carrier roller. It was found that the belt vibration is the principal source of dynamically accumulative errors since the influence of vertical and horizontal vibration on the measurement precision of weighing cell had been discussed.Kelvin model, based on local models, was constructed to make the analysis of the dynamics of an overall conveyor belt. Also the differential equations of motion of coupled vibration for the complete machine is established, whose results can be obtained by using Runge-Kutta method. The investigation shows the change in displacement and velocity in conditions of a uniform motion of the belt, and the influence of vertical and horizontal vibration of the belt on measurement of weighing transducer. the electronic belt weighing-scale system introduces a great dynamically accumulative error because of the change in forces exerted on carrier roller caused by coupled horizontal and vertical vibration, which also affects the sensor output. Moreover, the variation of belt tension for instance, deriving from dynamic loads relevant to the belt tension and the distribution of material on the belt, has a significant impact on measuring accuracy.Finally one major conclusion of this paper basis of static and dynamic analysis on the measurement system of an electronic belt scale and the suggestion and perspectives are put forward.