The Research On Printing Press Dynamic Charactistics Based On Vibration Test

Under the condition of high speed, the dynamic charactistics of the printing press are reflected through the vibration performance, which is also the main reason for limiting the machine speed increase, affecting the printing accuracy and accurring the machine malfunction.In this paper, under the methods of vibration test, the analysis and research of the printing press were carried out from the perspective of engineering test,and vibration-sensitive feature was extracted which reflected the strcture state of motion.Under the methods of modal analysis,inherent vibration charactistics of the mechanism strcture were studied. The results of the reaserch provide the basis parameters for modification of the printing press dynamic charactistics and vibration fault diagnosis, which has a certain theoretical and practical value.The main contents of the topics, are as follows:(1) With the help of the B&K vibration and noise measurement system, the vibration and noise test of the paper transmitting system for sheet-fed offset press was completed. The frequency and time domain correlation analysis of the test signals were carried out to determine the reasons of the excessive vibration, and the specific measures for improvement were put forward;(2) The vibration signals were extracted from a large number of test data which had strong correlation with the machine state of motion. In the further analysis, the typical mechanism vibration features of the gear mechanism, cam mechanism and printing cylinders were concluded, and the causes of vibration were also analyzed;(3) Not only the ANSYS finite element modal analysi method but also the experimental modal analysis method was used to carry out the modal test of the paper transmitting mechanism test bench, in which the modal frequency and the modal shape were obtained to identify weaknesses in the system vibration; (4) The test database of the printing press was eastablished. Based on the GUI of MATLAB, the test data analysis platform was developed to realize the large amounts of data batch processed result in reducing the data processing time and improving efficiency of the test. The test data analysis platform has been succssesfully used in the vibration test for one Printing Press Manufacture Group, the system was running stable and reliable during the entire test course.