基于形状约束的双质量飞轮设计理论研究

针对汽车双质量飞轮在低转矩小扭转角应具有柔性和高扭矩大扭转角应具有高反抗转矩的要求,结合产品研发的工程设计,对周向短弹簧双质量飞轮实现连续变刚度的设计目标进行研究与实践,创造性地提出通过改变初级飞轮内侧接触型线以构成形状约束,对构成形状约束曲线进行分析、比较,提出曲线的选择原则。构建基于形状约束的双质量飞轮转矩特性的分析模型,用仿真计算结果与试验进行对比。分析扭转刚度k1及k2对传动系一、二阶共振转速的影响,获得了k2对一阶共振转速影响不敏感、对二阶共振转速的影响明显的结论。在小扭转角条件下减小k1可使一阶共振转速远离怠速转速,对共振完全被隔离是有利的。对基于形状约束双质量飞轮所具有的扭转刚度及共振转速的力学特性进行实例分析,表明连续变刚度非线性扭矩特性具有优势,并能以简单的结构形式,实现兼顾转矩、刚度及隔振的设计期望。

Study on Design Theory of Dual Mass Flywheel Based on Shape Constraint

It is required that dual mass flywheel of small torsion and low torque should be flexible,while high torque and large torsion should be of high counter torque.According to this requirement,and combining with the engineering design of product R&D,research and practice are devoted into realizing the design object that the dual mass flywheel with circumferential short spring can reach the standard of continuous variable stiffness,which creatively propose the solution that shape constraint can be accomplished in the way of altering the internal contact profile of primary flywheel.Besides,selection principle of curve has been suggested by analyzing and comparing the structure of shape constraint.Based on the study of the torque characteristics of dual mass flywheel on shape constraint,the analytical mode has been built by comparing the simulation calculation results and the experimental measurements.Through analyzing the impact of torsional stiffness k1 and k2 on the driven system’s first and second-order’s resonance speed,it is concluded that k2 is not sensitive to the first-order’s resonance speed,instead,the second-order’s resonance can be affected evidently.On the condition of small torsion angle,the reduction of k1 can keep the first-order’s resonance far away from idling speed,which can keep the resonance being averted completely.Moreover,case study has been made in the mechanical characteristics lying in torsional stiffness and the resonance speed of the dual mass flywheel based on shape constraint,showing that the non-linear torque characteristics of the continuous variable stiffness is of great advantage that a simpler structure can fulfill the expectation of required torque,stiffness and vibration isolation.