机床动态切削建模中的相位关系

Phase Relation by Modeling of Dynamic Machining

通过分析以往实验数据、对比机床动态切削新老模型和引进闭环系统观点 ,证明只需要在切削过程子模型中考虑切削振动位移的影响 ,多质量多自由度整体模型会自动体现切削力与切削振动间的相位差别 .建立了相位差别同机床结构动态特性间的函数关系 ,阐明新模型还包含了再生效应、当前与先前切削振动间的相位差别 ,可以描述有限振幅不稳定切削 。

By means of analysing past experimental data, comparing a present modeling of dynamic machining with past ones and applying the viewpoint of closed loop interaction, it is verified that in the cutting process submodel only the effect of cutting vibration displacement needs to be considered and in the general model for multi-degree-of-freedom system the phase difference between cutting force and vibration is automatically embodied. The function relation between this phase difference and structural dynamic behaviour of machine is derived. It is demonstrated that the present modeling incorporates Tobias's regenerative effect, phase difference between the present and former cutting vibration, can describe the finite amplitude instability cutting and more generally expresses Tlusty's mode coupling effect, thus combines the main theories of historic researchers in itself. Its verification and practicality are further pointed out.