Dynamic Characteristics Analysis Of The Lower Platform Motion System Of Large-format Flat-pressure Die-cutting Machine

With the progress of society and the development of science and technology, as an important postpress equipment, automatic flat pressure die-cutting machine is developing toward the direction of high-speed, high precision and diversification. Domestic small-format models of flat pressure die-cutting machine are mostly mature, While the large-format models are improved to increase the size based on small-format models,the size is more dependent on experience and lack of necessary theoretical derivation and calculation. The motion system of lower platform is the center part of the die-cutting machine. Its motion performance directly determines the speed, accuracy and stability of large-format flat pressure die-cutting machine.In this paper, BMY-1900 die-cutting machine in Yutian Xingyuan Printing and Packaging Machinery Manufacturing Co.,Ltd. as the research object. Firstly, the motion parameters such as displacement, velocity and acceleration of each component under 4000 r / h rotational speed are obtained when the lower platform motion system was analyzed by plural vector method. The movement curve is drawn by MATLAB, and the movement rule of each component in one cycle is obtained, and the factors that affect the speed, precision and stability of die-cutting machine are pointed out. On the basis of kinematics analysis, the dynamics of multi-rigid body of the lower platform is analyzed by D'Alembert's principle, and the binding force and the driving torque required by the original motive force are solved under the biggest pressure 610 tons. On the basis of dynamic analysis, the finite element analysis was carried out of the key mechanism of the lower platform motion system by ANSYS software. The stress cloud and strain cloud are obtained and the weak link was improved. Based on the method of pressure identification of the die-cutting machine used by National Quality Supervision and Inspection Center of Printing Machinery, the new test method of the maximum die-cutting pressure of the die-cutting machine “stuffy car” is put forward. The method is simple and effective, can measure the maximum die-cutting pressure die-cutting machine accurately. Finally, the vibration test of the lower platform motion system of the die-cutting machine is carried out. The test results verify the weak structure of some components in the finite element analysis. Compared with the 1050 flat die cutting machine vibration test results, it can be found that the vibration of the points have become larger, but in a reasonable range. This paper validates the feasibility of the platform die-cutting machine on the basis of the small-format model, enlarges the structure and enlarges the format, and optimizes its shortcomings. The analysis method of this paper can be used for reference and guidance for the analysis and designing of the motion system of large-format flat- pressure die- cutting machine.