【作者】 罗勇；

【导师】 成刚虎；

【作者基本信息】 西安理工大学 ， 印刷工程， 2008， 硕士

【摘要】 平压平模切机是印后加工的重要设备。随着社会的发展和人们需求的提高,平压平模切机正朝着高速、高精度方向发展。主机模切机构是自动平压平模切机的核心部分,其机械性能的好坏,对模切机的工作能力、工作速度和模切质量起着至关重要的作用。但是,受传统习惯影响,认为模切机主要靠静压工作,人们主要对其运动特性和静态压力特性进行分析,而现实情况要远比这复杂的多。因此,有必要对模切机构的工作原理,运动学和动力学特性进行研究。其主要内容包括:1.运动分析是动力分析的基础,本文采用转换机构法和搜索法相结合的算法,对双肘杆机构进行运动分析,并利用MATLAB进行仿真,得到双肘杆机构在一个周期内的运动规律。2.假设双肘杆机构处于刚性环境下,基于达朗伯定理,对机构进行动态受力分析,得到机构各杆件在不考虑模切压力和考虑模切压力两种情况下,周期受力变化情况。通过对比表明,考虑模切压力作用的情况下,机构的受力状况发生很大变化,对机构产生不利影响。3.在考虑机构弹性的前提下,利用有限元法对双肘杆机构进行静态受力分析,得到在极限模切力的作用下,各杆件内部所受应力和位移改变情况。结果显示,当模切压力为300t时,连杆和肘杆的局部部位最大应力值远大于构件材料的许用应力值。4.对双肘杆机构进行模态分析,结果表明:考虑弹性情况下,机构的固有频率对机构的最终运动状况没有产生大的影响,可视其为等同处于刚性状态下考虑。5.考虑弹性的情况下,采用有限元的方法,利用ANSYS对双肘杆机构进行瞬态动力分析。根据所得数据分析知:双肘杆在运行过程中,由于模切压力的作用,动平台中间部位是比较薄弱的地方,受力后变形较大。更多还原

【Abstract】 The platen die-cutting machine is one of important devices in printing industry . With the rapid development of modern society and the improvement of people’s demands , high speed and high precision have become the most important trend of the platen die-cutting machine . The die-cutting mechanism is the core of the die-cutting machine , and its capability decide the work ability , the work speed and the qulity of the products . However , because of the traditional habit, people only analyzed the mechanism’s movement characteristic and the static power , and the fact is more intricate . Therefore , we should study the work principle , the movement characteristic and the dynamics characteristic of the die-cutting mechanism .The major content is as follow:1. The kinematics analysis is the basic of the dynamics analysis, in this article, the mechanism transformation method and the searching algorithm are used to analyze the movement of the dual-elbow-bar, and we get the rule of movement of the double-elbow-bar in a period by using the MATLAB software .2. Based on the D’Alembert principle, the rigidity dynamics analysis of the dual -elbow-bar is disposed to get the value of the power in a period, on the assumption that the mechanism is rigid. And the contrast indicates that the value of the power will be increscent largely , in the case of considering the press, which will bring the negative effect.3. The elasto-statics analysis of the dual-elbow-bar is disposed to get the value of the stress and the distortion of every bar, in the case of considering the mechanism’s elasticity . And the result indicates that the stress of the parts which belongs to the linkage and the elbow-bar mechanism is bigger than allowable stress when the press becomes 300t.4. The mode analysis on the dual-elbow-bar indicates that the natural frequency has no important relation to the final movement of the dual-elbow-bar mechanism, in the case of considering the mechanism’s elasticity, and we can think of the mechanism as rigid .5. In the case of considering the mechanism’s elasticity, the finite element method is used to analyze the transient dynamics by the ANSYS software .And the data shows that ,if the press is brought to bear, the middle part of the moving platform mechanism is changed easily, when thedual-elbow-bar is running.更多还原