含间隙运动副机构的动力学特性研究

Dynamic characteristics of mechanisms with revolute clearance joints

为了研究含间隙运动副机构的动力学特性的影响,综合考虑转动副轴向尺寸、材料非线性系数以及碰撞过程能量损耗等因素,建立了一种改进的非线性接触碰撞力模型,同时提出了一种用于描述间隙处摩擦作用修正的库伦摩擦模型。以曲柄滑块机构为研究对象,将上述接触碰撞力模型和摩擦力模型嵌入系统动力学模型中,进行动力学仿真分析,研究不同间隙、驱动载荷及摩擦系数对机构动力学特性的影响,并将仿真结果与试验测试数据进行对比分析。结果表明:基于改进的非线性接触碰撞力模型、修正的库伦摩擦力模型仿真计算结果,与实验结果吻合较好,能够准确、有效地描述含间隙运动副机构的动态特性。

In order to study the dynamic characteristics of mechanisms with revolute clearance joints,an improved nonlinear contact impact face model was established here,the axial dimension was introduced into the model,and the friction force in clearance joints was described using a modified Coulomb friction model. As an example,a slider-crank mechanism was taken as a study object,the two models mentioned above were introduced into the system＇s dynamic equations. The effects of clearance,driving load and friction coefficient on the dynamic characteristics of the mechanism were analyzed with simulations. The simulated results were compared with those of tests. The results showed that the simulation results agree well with the test ones,the two models can accurately and effectively describe the dynamic characteristics of mechanisms with revolute clearance joints.