汽油机正时链轮系统设计优化与动力学特性研究

Dynamic Performance Research and Design Optimization of Gasoline Engine Timing Sprocket

针对某汽油机链条啮合接触力较大等问题,基于正时链轮系统多体动力学模型提出了新设计方案,并通过CAE仿真对新、旧两种链轮传动系统结构方案进行高转速时的动态仿真对比研究。分析表明,新方案可有效的降低链节接触冲击力、减少链轮及链节角速度波动。同时,针对新方案动力学模型,对比了考虑与不考虑转速波动时的链系动态结果。研究发现,由曲轴扭振引起的转速波动对链轮角速度影响较大,而对链节接触冲击及其角速度影响较小。

To reduce the excessively high chain mesh contact force of a gasoline engine, a new design plan based on multi-body dynamic model of timing sprocket was proposed. Dynamic simulation between new and old sprocket train plans in high speed was simulated and compared by CAE. Research results showed that the new plan could lower chain contact impact force and angular velocity fluctuation of sprocket and chain effectively. Meanwhile a comparison was made to dynamic resuks of chain gear with/without considering speed fluctuation. Research showed that crankshaft angular velocity fluctuation affected sprocket angular speed, while little affection on chain link contact impact and angular velocity.