基于最低制造成本的一种公差优化设计法

A discrete optimal tolerancing approach based on the process capabilities

提出一种基于加工能力约束最低制造成本的公差优化设计方法 .利用加工的标准偏差估计值和制造成本 公差关系模型 ,以装配功能公差链、加工合格率以及加工方法的经济公差最大极限为约束条件 ,通过分别建立和求解公差优化的初始模型和最终模型 。

A design approach to discrete hierarchy optimal tolerance based on the process capability is proposed. Through the use of estimation value of standard deviation of the actual manufactured dimensions and related functions between manufacturing cost and tolerance and formulation of the constraint equations of the assembly functional tolerance chins, the acceptable manufactured probability, the economical tolerance maximum bounds of the machine tools and the original and final optimal model are established and solved respectively, and the optimal tolerances are obtained. In original optimal model the objective function aims at minimizing the total manufacturing cost with different weight factors. The final model attempts to maximize the ratio of the final optimal tolerances to the ones relative to the original solution. A practical example is used to verify the usefulness of the proposed approach.