弹性曲柄滑块机构的运动精度可靠性分析

Reliability Analysis of Kinematic Accuracy for Elastic Slider-Crank Mechanism

将弹性曲柄滑块机构的杆长、截面尺寸、铰链间隙、质量密度、弹性模量等几何、物理参数均视为随机变量,对机构输出运动进行了静态和动态误差分析。应用微小位移的线性叠加原理分别对静态、动态误差进行了综合,建立了机构输出运动精度可靠性分析模型。通过算例,考察了机构输出运动精度可靠度的影响因素,结果表明随着机构转速的提高,机构的动态弹性变形将成为影响机构运动精度可靠性的主要因素。

This paper deals with the static and dynamic output kinematic accuracy of a group of elastic slidercrank mechanisms with the same design parameters by taking the bar length, joint-gaps, mass density, interception and physical parameters as random variables. According to the principle of linear pile-up of small displacement, the static and dynamic output kinematic errors are synthesized, and the reliability model of the kinematic accuracy of the mechanism is built. Through an example, a study of the influencing factors on the reliability of the output kinematic accuracy of the mechanism is made, the results obtained reveal the following factwith the increase of crank＇s rotating speed, the dynamic elastic deformation of the mechanism becomes the principle factor that effects the reliability of the output kinematic accuracy of the mechanism greatly.