六连杆冷温锻压力机传动机构优化设计

Optimal design of transmission mechanism for a six-link cold and warm forging press

为改善冷温锻压力机滑块的运动学曲线、提高锻件质量,对传动机构的杆系参数进行优化。在建立了六连杆冷温锻压力机传动机构的运动学模型的基础上,结合工程实际设计约束条件,以机构的最大高度、急回特性和最大加速度为优化目标,采用线性加权的方式得到统一的目标函数,并使用惩罚函数和复合形法相结合的优化算法求得工程最优解。在构造多目标函数的过程中,提出了一种量纲转换函数,并将优化后的主要技术指标和滑块运动学曲线与常见的量纲转换函数优化后的结果作对比,发现机构的最大高度降低了3.6%,回程时间缩短了10.3%,下死点前15 mm处的速度减小了12.4%,说明了该量纲转换函数相比于常见的量纲转换函数具有优越性,有一定的参考价值。

In order to improve the kinematics curves of slider for cold and warm forging press and the quality of forgings,the link parameters of transmission mechanism were optimized.Then,based on the kinematics model of transmission mechanism for six-link cold and warm forging press,combining with the actual engineering design constraints,taking the maximum height,the rapid return characteristics and the maximum acceleration as optimization targets,the unified objective function was got by the method of linear weighting,and the engineering optimal solution was obtained by the optimization algorithm combining penalty function and complex method.Furthermore,in the process of constructing the multi-objective function,a dimensional conversion function was put forward,and the optimized main technical indexes and the kinematics curves of slider were compared with the results optimized by common dimensional conversion function.The results show that the maximum height of mechanism is reduced by 3.6%,the return time is shortened by 10.3%,and the speed at 15 mm before the bottom dead point is reduced by 12.4%,which show that the dimensional conversion function is superior to the common dimensional conversion function and has certain reference value.