基于时变切削力的滚齿振动动力学模型

Dynamics Model of Gear Hobbing Vibration based on Time-varying Cutting Force

滚齿加工过程中的时变切削力会引起颤振,影响加工质量和工件精度。为了分析滚刀-工件系统的振动特性,根据金属切削理论,提出了考虑单刀齿和双刀齿切削的时变切削力计算方法。同时,建立了4自由度滚刀-工件的滚齿振动动力学模型,获得了不同转速工况对系统振动特性的影响,并进行了滚削振动测试实验;通过对现场实验数据与理论计算结果对比分析,验证了动力学模型的正确性。研究结果表明,新的计算方法能够准确计算滚刀和工件的振动特性,可为研究切削颤振机理和加工系统状态监测提供依据。

The time-varying cutting force in the process of gear hobbing will cause chatter and affect the quality and the precision of workpiece. To analyze the vibration characteristics of hob and workpiece system,according to the theory of metal cutting,a calculation method of the time-varying cutting force is proposed,by considering single tooth cutter and double-tooth cutter. At the same time,a dynamics model of gear hobbing vibration with four degrees-of-freedom is established,the effects of different rotational speed on the vibration characteristics are obtained. Also,a vibration experiment of gear hobbing is carried out,and the dynamics model is proved to be correct based on contrastively analyzing the experimental data and the results of theoretical calculation. The results of study show that the new calculation method can calculate the vibration characteristics of the hob and workpiece accurately,which can provide a basis for studying the mechanism of cutting chatter and monitoring the conditions of machining system.