This paper is devoted to overcoming the walking wheel vulnerability to frequent broken teeth resulting from the complex meshing characteristics behind coal shearer walking wheel and pin gear;and eliminating the failure due to abnormal wear.The research using relative motion theory and Newton's second law consists of investigating the mechanics model for elastic connection between the walking wheel and pin gear,rack and rack;providing pin tooth meshing force expression and establishing the dynamics equation of coal running gear;developing the varying curve of the wheel angular velocity,pin tooth meshing force,and the pitch using dynamic simulation method.The research demonstrates that pitch changes have a significant impact on gear meshing force and speed fluctuation and;a walking wheel has a smallest speed fluctuation value,only 2％,such as occurs when the teeth meshing force has a maximum peak occurring near the connection between the two teeth track where a walking wheel experiences a most frequent speed fluctuation,combined with the minimum rack pitch;in this case,pin pitch ranges from the minimum value of 143 mm to the maximum value of 158.5 mm.The results may serve as certain reference for studying the dynamic characteristics of the walking mechanism behind shearers,improving the way walking wheels and racks are subjected to loads,and improving the service life of the walking wheel racks.%针对采煤机行走轮与销齿复杂的啮合特性导致的行走轮经常发生断齿,以及非正常磨损等失效状况,采用相对运动理论和牛顿第二运动定律,研究行走机构行走轮-销齿、齿轨-齿轨弹性连接的力学模型,给出销齿啮合力表达式,建立采煤机行走机构的动力学方程;采用动力学仿真法,得到行走轮角速度、销齿啮合力变化曲线及节距变化曲线.研究表明:节距变化对销齿啮合力和速度波动影响显著;销齿啮合力最大峰值出现在两节齿轨连接处附近,且该区域行走轮速度波动最频繁,齿轨节距最小时,行走轮速度波动值较小,仅为2％;销齿节距最小值为143 mm,最大值为158.5 mm.该结果对研究采煤机行走机构动力学特性、改善行走轮及齿轨受力、提高行走轮使用寿命具有一定参考价值.
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