振动拉削双阀激振系统输出波形稳定性分析及实验研究

摘要

为了分析振动拉削系统在加工过程中电液激振输出幅值稳定性问题,首先引入流量耦合线性模型和拉削负载力模型,构建了双阀激振系统的传递函数,推导了系统输出位移和输出力的时域响应函数;再利用MATLAB仿真计算及绘制开环系统的Bode图和幅值时域响应曲线;最后,利用自行研制的振动拉削实验平台所测得的激振器输出幅值与仿真结果进行对比分析,研究结果表明:激振信号的频率会影响输出波形的平衡位置及波动幅值,激振信号频率越高,输出波形越容易调节;而拉削负载力主要影响输出波形的振荡次数,负载力越大,输出波形越不稳定.因此,为了使拉削过程中激振输出波形更加稳定,一方面可适当提高激振缸缸径和行程的比值,以增大系统极限响应频率,另一方面需蓄能装置或大流量型开关阀平衡激振缸容腔压力配比.%In order to investigate the output amplitude stability of an excitation system during vibration broaching,a transfer function of a dual-valve excitation system was established by considering the flow coupled linear model and the broaching force model.And the time domain response function of output force and displacement was obtained based on the transfer function.Then,the simulated results of aforementioned function were calculated by MATLAB,including Bode diagram and the response curve of time domain.Finally,the experimental data were compared with simulation results,which were obtained from the novel vibration broaching platform.The results show that the frequency of the excitation signal affects the balance position and the amplitude of the output waveform.The higher the frequency of the signal is,the easier the output waveform can be adjusted.The oscillation frequency of the output waveform is mainly affected by the broaching force.The greater the force was,the more unstable the output waveform was.Therefore,to make the output waveform more stable,the ratio of vibration cylinder bore and stroke should be improved,which can increase the response frequency.On the other hand,the energy storage device and flow type valve should be added,which can balance the pressure ratio of vibration cylinder cavity.