Simulation And Research On Gear Transmission System Of Coal Mining Machine Cutting Unit

Coal resources are strategic resources in our country and the degree of mechanization of coal mining resources is an important indicator of a country’s technological development.Furthermore,safety,efficiency and reliability index of coal mining machinery are important parameters to measure a country’s technological progress.The rocker arm gear transmission system of the cutting unit is the core component of the shearer,which always fails and causes downtime in actual production,so simulation research on rocker arm gear transmission system of shearer cutting unit is of vital importance for designing shearer with high performance.A domestic shearer cutting unit gear system is taken as the model and simulation study on the structure and motion characteristics is conducted.The main tasks include:(1)According to design drawings of a type of gear transmission system of shearer cutting unit,determining the structure parameters of rocker arm gear transmission system of shearer cutting unit.Using the modeling software Pro/E to build parametric solid model and the simplified model for simulation and finite element analysis.Taking errors that may appear in the actual assembly into consideration,a solid model of transmission gears with assembly errors is established.(2)Finite element analysis of the gear transmission system of shearer cutting unit is studied with Workbench.Making static contact analysis of the gear transmission system,comparing the contact stress with traditional Hertz contact algorithm to verify the accuracy of static contact analysis.The influence of friction factor between tooth surfaces on contact stress is studied,getting the conclusion that reducing the friction factor can bring less negative effect caused by friction through ways such as lubrication.(3)Contact stress analysis of high-speed gears is studied considering assembly error.A case is that the axes are not parallel in the horizontal plane,the other case is that the axes are not parallel in the vertical plane.Then getting the influence of gear axis non-parallelism error(ie assembly error)on the maximum contact stress,and thus giving the axis parallelism error allowed for high-speed gears.(4)Dynamic characteristics analysis of transmission gears of shearer cutting unit is studied by using finite element method.By free modal analysis and constraint modal analysis of the rocker arm gear transmission system of shearer cutting unit,inherent characteristic of the gear transmission system is obtained,and input frequency range is got to avoid resonance.Making transient dynamic analysis in high-speed area of gear transmission system of shearer cutting unit,to get how the maximum contact stress changes under actual working conditions,which provides important reference for design of gear transmission system of shearer cutting unit.