【作者】 刘琳琳；

【导师】 成刚虎；

【作者基本信息】 西安理工大学 ， 制浆造纸工程， 2007， 硕士

【摘要】 胶印中,压印滚筒完成图文转移,是胶印机的核心部件,而压印滚筒在印刷压力作用下的挠曲变形导致了印刷压力分布不均匀。本文以J2108型胶印机压印滚筒为研究对象,通过有限元分析获得滚筒动静态挠曲特性,提出用主动补偿方法改善滚筒挠曲变形,并仿真分析了补偿特性。本课题研究主要成果如下:(1)利用Solidworks2006软件建立J2108型胶印机压印滚筒三维模型,利用有限元分析软件ALGOR V18对滚筒在印刷压力和重力载荷作用下的挠曲变形进行有限元分析,得到滚筒轴向、周向挠曲变形曲线,推导出滚筒挠曲变形三维模型,表明印刷压力不仅在滚筒轴向不均匀,而且圆周方向呈波状起伏;(2)提出用主动补偿方法改善胶印机压印滚筒挠曲变形,基于08机压印滚筒改造设计挠性压印滚筒,通过对补偿机构仿真分析,表明主动补偿能有效减小滚筒挠曲变形,并优化了结构方案;(3)通过对滚筒挠曲变形作动态分析,模拟滚筒滚压过程,说明滚筒在动态压印下挠曲变形呈简谐振动形态,印刷速度越高,印刷压力变化越大,从而获得滚筒动态特性;(4)将滚筒挠曲变形作为变截面简支梁问题研究,编写了印刷滚筒挠曲变形程序,计算表明:滚筒挠曲变形研究中重力载荷影响不可忽略。本课题通压印滚筒挠曲变形的分析,可以获得滚筒在印刷压力作用下的动静态工作特性,为滚筒结构的改进设计提供指导性意见,所提出的主动补偿方法可以为滚筒结构的创新设计提供思路。更多还原

【Abstract】 In offset, impression cylinder is critical component in transfer process of graphics context, and its flexural deformation results in unhomogeneity of printing pressure distribution. This paper studies on the impression cylinder of J2108 offset press. With finite element method, deflection character of cylinder is achieved in static and dynamic load. Active-compensation to improve flexing-change of cylinder is bring forward, and its compensation character is simulated.The main work and results are as follows:(1)Three-dimensional model is created on the impression cylinder of J2108 offset press by Solidworks2006. The finite element analyses are employed in ALGOR V18 to research the flexural deformation of cylinder in printing pressure and gravity working, deflection curves are get in axial and circumferential, and the 3D model on deflection of cylinder which indicates printing pressure is not only no-uniform in axial, but also wave-like periods in circumferential.(2)Active-compensation to improve flexing-change of cylinder is bring forward, and flexible cylinder is designed based on impression cylinder of J2108.The simulation analysis of compensation mechanism indicates that active-compensation can effectively improve the deflection, and construction scheme is optimized.(3) Dynamic analysis is carried on in this paper, and rolling process is simulated. By transient response analysis, it is indicated that the deflection is simple harmonic vibration form in dynamic pressure, the higher the printing speed, and the larger the pressure-change. Hence the dynamic character ofcylinder is acquired.(4)The deflection of cylinder is researched as simply supported beam with variable cross section, and calculating program is achieved on deflection of cylinder, the result states: influence of gravity is an important part in research on deflection of cylinder.In this research, we acquire static and dynamic character of cylinder in printing pressure, which can direct improved design to cylinder structure, and active compensation can supply a new method to innovative design.更多还原