Study On Deflection Of Impression Cylinder And Active Compensation Method

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.