浮框驱动弛张筛的振动特性分析

Analysis on vibration characteristics of flip-flop screen driven by floating frame

浮框驱动弛张筛是将激振力直接驱动浮动筛框的一款新型振动弛张筛。介绍了浮框驱动弛张筛的结构及工作原理,建立了该筛机的力学模型,并推导出振动系统的二阶线性常系数非齐次微分方程组,求解出固定筛框和浮动筛框受迫振动的振幅;对传统弛张筛和浮框驱动弛张筛的振动特性进行对比分析,确定出浮框驱动弛张筛的工作频率区域;通过分析y轴振动情况,解释了传统弛张筛和浮框驱动弛张筛在y轴振动不同的原因,并用DASP测试系统进行检测,同时还讨论了传统弛张筛和浮框驱动弛张筛的驱动功耗。结果表明:当浮框驱动弛张筛的工作频率达到二阶共振频率附近时,完全可以实现弹性筛板的弛张运动,其在y轴的振动与传统弛张筛存在着差异,而且所需激振力更小,节能效果更显著。

The flip-flop screen driven by floating frame is a new-type vibratory flip-flop screen whose floating frame is directly driven by excitation. In the paper, the structure and the working principle of the flip-flop screen driven by floating frame was introduced, and its mechanical model was set up. And then, second-order linear constant-coefficient nonhomogeneous differential equation set was derived, and the vibration amplitude of the fixed frame and the floating frame was figured out. In addition, the traditional flip-flop screen was contrasted with the flip-flop screen driven by floating frame in the vibration characteristics, and the range of the operating frequency of the flip-flop screen driven by floating frame was identified. After the analysis on vibration state along axis y, the vibratory reasons of the traditional flip-flop screen and the flip-flop screen driven by floating frame along axis y were explained. Finally, DASP test system was applied to conduct test, and the driving energy consumption of the traditional flip-flop and the flip-flop screen driven by floating frame was discussed. The results showed： while the operating frequency of the flip-flop screen driven by floating frame neared the second-order resonance frequency, the tension and relaxation movement of the elastic sieving plate completely realized; its vibration along axis y differed from that of the traditional flip-flop screen, and less excitation was needed, energy-saving effects was more remarkable.