Aiming at the problems of low material looseness, limited utilization rate of screen surface and difficult to effectively improve the screening rate of traditional vibrating screen when screening difficult-to-screen materials and wet materials, a four-axis inertial composite excitation model is constructed based on Lissajous vibration synthesis principle and mechanical analysis. By forcing the gear transmission to control the frequency ratio and phase difference of the excitation model, a variety of Lissajous composite vibration modes are accurately realized. The four-axis inertial composite excitation model is placed in the vibrating screen to construct a composite vibrating screen, and the discrete element method is used to simulate the screening process of the material group on the surface of the vibrating screen. An experimental platform was built to carry out screening experiments of materials with different particle sizes and different water mass fractions. The results show that the composite vibrating screen can apply an exciting force along the width direction of the screen surface to the material on the screen, effectively increase the reciprocating motion of the material, make the material more loose, and significantly improve the screening efficiency.
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