重载卡扣锁紧机构力学分析与优化设计

Mechanical analysis and optimization design of snap-fit-type locking mechanism under heavy load condition

采用有限单元法、叠加法、Hertz线接触理论进行悬臂卡扣式锁紧装置二维模型解锁力、正应力、接触压力计算,重点考虑卡扣纵向截面和轴向载荷关于其中性轴不对称对弯曲变形的影响。在试验仿真分析合理的基础上,基于正交试验利用仿真工具研究了锁紧装置二维模型与三维模型的关系,给出了理论计算经验修正系数。对锁紧装置进行了优化设计,接触区域采用椭圆弧线过渡,增加卡扣根部截面高度,在正常工作和扣入量增加2 mm的非正常工作时,相较试验模型更加安全可靠。

Aiming at the cantilever snap-fit-type locking device used to reliably lock the heavy motor mover,the unlocking force,normal stress and contact pressure of the two-dimensional model of the locking device were calculated based on the finite element method,superposition method and Hertz line contact theory,mainly considering the influence of the asymmetry of longitudinal section and axial load about neutral axis of the buckle on the bending deformation.On the basis of the experiment to verify the rationality of the simulation analysis,the relationship and difference between the two-dimensional model and the three-dimensional model of the locking device were studied by using the simulation tool based on the orthogonal test,and the empirical correction coefficient of theoretical calculation was given.The locking device was optimized,such as the contact area was adopted elliptical arc transition and the height of the root section of buckle was increased,which is safer and more reliable than the experimental model during normal operation and abnormal operation with an increase of 2 mm in the deduction amount.