刚柔耦合链啮合传动系统的动力学建模与振动失效分析

Dynamics modeling and vibration failure analysis of a rigid-flexible coupled chain meshing drive system

刮板输送机链啮合传动系统具有刚柔耦合的结构特征,运行过程除传递驱动力还需承担物料的牵引负载,在链传动多边形冲击与时变负载的耦合影响下容易发生掉链故障。针对此问题,构建了链环-链轮-轴承刚柔耦合非线性动力学模型,分析了链轮齿数、负载等对传动系统振动冲击特性的影响规律,研究了振动冲击导致的掉链故障机理,确定了啮合传动系统的振动失效阈值,通过开展传动试验验证了模型的有效性。研究结果表明:链轮转速达到接近840 r/min时系统发生共振;啮合传动系统在4个位置可能出现掉链故障,分析发现啮入的振动失效阈值低于2 mm,最容易发生掉链故障;选用齿数较多的链轮,可有效降低链啮合传动系统振动冲击,提高传动系统的运行稳定性。

The scraper conveyor chain meshing transmission is a rigid-flexible coupled drive system,which not only transmits the driving force but also bears the traction load.During operation,it is easy to fall off the chain under the coupled influence of the polygonal impact of the chain drive and the time-varying load.Regarding this issue,a nonlinear rigid-flexible coupled model of the chain ring-sprocket-bearing system was constructed,and the influences of installation size,sprocket teeth number,and load on the vibration characteristics were analyzed.Then,the failure mechanism caused by the vibration impact was investigated.The vibration failure threshold of the meshing transmission system was determined.The validity of the dynamic model was verified by a transmission test.The research results show that the system resonates when the sprocket speed reaches close to 840 r/min.The system may have chain dropping faults in four positions,and the vibration failure threshold of meshing is lower than 2 mm,which is the most likely to lead chain dropping faults.The selection of sprocket with a larger number of teeth effectively reduces the vibration impact of the chain meshing transmission system,and improves the operational stability of the transmission system.