混合动力车用三缸汽油机曲轴平衡设计

Crankshaft Balanced Design of Gasoline Engine for Hybrid Vehicle

汽车动力系统发展日益多元化,混合动力效降低燃油消耗及排放,同时有效的解决了纯电动汽车的里程焦虑问题,市场份额不断增加。由于混合动力发动机运行工况较传统发动机更窄,更多的利用自然吸气发动机的高效率区。但是,由于混动系统较传统动力增加了电动系统,为解决整车布置问题,需要匹配更紧凑的三缸发动机。本文基于四缸自然吸气发动机,研究三缸自然吸气发动机曲轴结构及平衡重的设计,并对曲轴的扭振进行评估。结果表明:采用四平衡重结构并将平衡重偏心30°布置,可以使得在最小力偶的情况下,实现旋转惯性力矩的平衡;该三缸自然吸气发动机曲轴扭振的最大振幅为0.070 deg,满足扭振评价要求。

The development of automobile power system is becoming more and more diversified.The hybrid efficiency reduces fuel consumption and emissions.At the same time,it effectively solves the mileage anxiety problem of pure electric vehicles,and the market share is increasing.Because the operation condition of the hybrid engine is narrower than that of the traditional engine,more efficient areas of the naturally aspirated engine are used.However,because the hybrid system adds an electric system to the traditional power,in order to solve the vehicle layout problem,it needs to match a more compact 3-cylinder engine.Based on the 4-cylinder naturally aspirated gasoline engine,this paper studies the design of crankshaft structure and balance weight of 3-cylinder engine,and evaluates the torsional vibration of crankshaft.The results show that the balance of the moment of inertia can be achieved with the minimum couple of forces by adopting the four balance weight structure and arranging the balance weight at an eccentricity of 30°.The maximum amplitude of the crankshaft torsional vibration of the three cylinder naturally aspirated engine is 0.070 deg,which meets the requirements of torsional vibration evaluation.