| The coal is main energy in our country, and it plays an important strategic role in Chinese economic development. Shearer is a safe and efficient equipment in modern coal mine, which has attracted more and more attention. As a key compound mining equipment, the cutting part load impact is passed through the rocker arm drive system in Drum shearer. Through the analysis and research of the dynamic characteristics of the rocker gear transmission system, it is useful to improve the life and reliability of Shearer, to realize high production and efficiency of coal mining. Based on the theory of vibration and modal theory, the parameterized modeling, virtual prototype technology, finite element analysis, a study is made to analyse dynamic characteristics of rocker transmission system.According to the theory of mechanical vibration, based on the analysis of the motion of the planetary gear, the pure dynamic model of the compound planetary gear of the rocker transmission system is established by using the lumped parameter method. The time varying meshing stiffness of gear is calculated by energy method. The Fourier series method is used to solve the planetary gear dynamics equations and calculate the dynamic response of the gear and the dynamic meshing force of gear pair. The result shows that the gear vibration is smaller, thus it meets the design requirements.According to the dynamic equations of compound planetary gear, its inherent characteristic is analyzed. The ADAMS is also applicated to verify the compound planetary gear natural frequency. The influence of design parameters on natural frequency is studied, and the sensitivity of each parameter to natural frequency is calculated, which can provide a theoretical basis for predicting the dynamic characteristics of gear transmission system at the design stage.According to the formation principle of involute gear, the parametric model of involute changing gear is established by means of Pro/E software. A 3D model of rocker arm drive system is built by virtual assembly of gear. Based on the multi-body dynamics theory and virtual prototyping technology, the dynamic simulation model of shearer rocker arm drive system is established by using ADAMS. According to the load characteristics of the shearer rocker arm system, the dynamic analysis of the load is carried out and the results is the motion of each gear, vibration characteristics of compound planetary gear components, dynamic meshing force of compound planetary gear. Through comparing the simulation results and the theoretical calculation, they are basically the same.Finally, the static finite element analysis of the rocker arm transmission system is carried out by using the ANSYS software. The maximum stress value of the internal and external gear pair of the planetary gear is calculated and compared with the allowable value of the material, which indicates that the material can meet the design requirements.At the same time, the ANSYS is applicated to analyse the modal of rocker box, obtaining the first 10 order inherent frequency, vibration type and rocker arm of the maximum deformation position, which shows that the excitation frequency of the rocker arm is away from the inherent frequency, the material meets the strength requirement and rocker arm can work normally. |
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