大型矿用电铲推压减速器齿轮齿向修形研究

RESEARCH ON AXIAL MODIFICATION OF CROWD REDUCER GEARS OF LARGE MINING ELECTRIC EXCAVATOR

大型矿用电铲推压减速器齿轮为低速重载硬齿面齿轮,挖掘过程中不可避免会出现齿轮偏载情况,通过对其齿向修形可实现提高其承载能力、改善其接触状态的目的。利用齿轮薄片理论模型,将电铲挖掘过程的统计平均载荷作为修形参考载荷,以电铲挖掘过程中统计平均推压力最大位置的齿轮接触应力最小为目标,进行推压减速器两级小齿轮(主动轮)的齿向斜度修形,进而以各挖掘位置均不会出现过大的齿面边缘载荷为目标,进行两级小齿轮的齿向鼓形修形。相比修形前,已修形的齿轮在电铲挖掘过程中所受最大应力(包括齿面接触应力与齿根弯曲应力)明显减小,并且齿面边缘接触状况明显改善。当修形后齿轮受到电铲挖掘过程中统计最大载荷作用时,齿轮应力值依然小于其许用应力。仿真研究结果表明,大型矿用电铲推压减速器齿轮齿向修形,对提高齿轮承载能力和改善齿面接触状况均具有积极意义。

The crowd reducer gears of large mining electric excavator are low speed,heavy-duty and hard surface gears.In the mining process,the phenomenon of gear unbalanced load is inevitable.Through the modification of gears,it is possible to improve its carrying capacity and contact state.Using the thin slice gear model,statistical average load of excavator mining process is taken as the reference load of modification,the minimum contact stress of gears at the excavator mining position withmaximum statisticalcrowd force is regarded as the objective,the slope modification of the two stage pinion(driving wheel) of the crowd reducer is carried out.Further,no edge load at tooth surface in each mining location is regarded as the objective,the crown modification of the two stage pinion of the crowd reducer is carried out.In the process of excavator mining,compare with pinion without modification,the maximum stress(including contact stress of tooth surface and bending stress of tooth root)of thepinionwith modification decreases significantly,and the edge contact condition of tooth surface is obviously improved.After modification,when the gear is subjected to the statistical maximum load of excavator mining process,the stress value of the gearis still less than the allowable stress.Simulation results show that,axial modification of crowd reducer gears of large mining electric excavator has positive significance for improving carrying ability and contact condition of gears.