在研究某些机械自激振动时 ,本文以初轧机为例 ,考虑了连接轴可动性和间隙对初轧机自激振动的影响 ,提出了一个新的力学模型 ,从理论分析出发 ,建立了带有可动边界和间隙情况下的初轧机自激振动微分方程式 ,探讨了该系统振动特性 ,得到消除自激振动的条件。所得到的结果可供生产实际参考 In the study of some mechanical self-excited vibration, taking the initial rolling mill as an example, a new mechanical model was proposed considering the influence of the connection axis mobility and clearance on the self-excited vibration of the initial rolling mill. Based on the theoretical analysis, The self - excited vibration differential equation of the initial rolling mill with movable boundary and clearance is discussed. The vibration characteristics of the system are discussed and the condition of eliminating self - excited vibration is obtained. The results obtained for the production of practical reference