基于稳健性分析的轮转机折页机构优化设计

Optimal Design of the Web Press's Fold Mechanism Based on Robustness Analysis

随着印刷机械速度的提高,在印刷机械设计时,高速与高稳定性已成为相互制约的两个方面。轮转机是印刷设备中速度最高的大型印刷设备,其折页机构对机器运转速度的制约最为显著。为提高轮转机折页机构的速度和稳定性,提出运动精度和动力精度两个稳健性指标。通过对高速运行状态下轮转机折页机构工作状态进行动力学分析,建立其动态响应与设计参数的动力学模型。在动力学模型基础上,建立基于稳健性分析的优化设计模型,以寻求稳健性最佳的设计变量,达到改善轮转机折页机构动力学性能,在保证其折页精度的前提下,提高机构长期高速运转稳定性的目的。设计实例表明,在设计变量稳定的情况下,稳健设计与轨迹优化设计的机构运动性能差别不大,但稳健设计的机构动力学性能要远远优于轨迹优化设计。在设计变量发生微小改变的状态下,运用稳健设计方法所得参数能使机构保持良好的稳定性。

With the increasing of printing machine＇s working speed,high-speed and high stability are the two mutual restraint aspects in modern printing machine design.The web press is large-scale equipment with the highest printing speed,and the stability of fold mechanism is the most significant constraint to speed.In order to increase the mechanism speed and stability, the two robust criterions,kinematics and dynamics precision,had been proposed.Through the kinetic analysis to the fold mechanism of web press,the dynamic model of the mechanism response to design variables had been established.By the model,the optimization model had been established based on robust analysis to seek the design variables with the best robustness, the goal of increasing the mechanical long-term stability in high speed could be attached in the condition of ensuring the fold precision.The design example showed that in the case of the stable design variables,the kinematics performances of robust optimization design and trace optimization design are slightly different,but the dynamic performances of robust optimization design are much better than that of trace optimization design,and in the case of the design variables＇ slight changes,robust optimization design can make the mechanism＇s dynamic performances still maintain.In short,robust optimization design is a good way to increase the stability of machine.