变频调谐的动力减振镗杆的设计与仿真实验

针对大长径比镗杆刚性差,在镗削加工过程经常出现颤振,难以保证加工质量和影响刀具寿命,文章设计结构新颖的变频调谐动力减振器。通过不同角度的弹性质量块位置安装可改变减振器的固有频率;依据减振理论分析不同固有频率比下系统幅频特性曲线的变化规律,运用ANSYS有限元计算所设计的弹性质量块安装不同角度的减振器的一阶固有频率值,确定固有频率比的变化范围,得到减振镗杆的最佳参数;通过ADAMS仿真实验,验证抑振效果,结果表明:减振器安装在最佳位置时的频响函数峰值得到较大削弱,由未安装减振器时的高幅值单峰变为安装减振器之后的低幅值双峰,安装减振器的镗杆的减振幅度约为未安装的两倍以上。

Design and Simulation Experiment of Frequency Conversion Tuned Dynamic Vibration Absorber Boring Bar

In view of the poor rigidity of the boring bar with large ratio of length to diameter,the chatter often occurs in the boring process,which is difficult to guarantee the machining quality and affect the tool life,In this paper,A novel variable frequency tuned dynamic shock absorber is designed.The natural frequency of the shock absorber can be changed by installing the elastic mass block at different angles.According to the theory of vibration absorption,the changing law of the amplitude frequency characteristic curve of the system under different natural frequency ratio is analyzed.The ANSYS finite element method is used to calculate the first-order natural frequency value of the designed elastic mass block with different angles of the shock absorber,determine the change range of the natural frequency ratio,and obtain the best parameters of the vibration absorption boring bar.Through the ADAMS simulation experiment,the effect of vibration suppression is verified.The results show that the peak value of the frequency response function is greatly weakened when the shock absorber is installed in the optimum position.The peak value of the frequency response function changes from the single peak of the high amplitude when the shock absorber is not installed to the double peak of the low amplitude after the shock absorber is installed.The vibration reduction amplitude of the boring bar with the shock absorber is about twice as large as that without the shock absorber.