Vibration identification of flexo printing machine by analyzing the printed samples

To avoid the difficulty in measuring the cylinder vibration in the flexo printing machine, this paper presents a new method to identify the vibration frequencies of the cylinders by analyzing the printed samples. The stripes on the printing samples are used as measured signals, and the vibration frequencies can be found out with the help of the Wavelet Analysis. The identified results are compared with an experimental modal analysis, which shows that the three identified frequencies are the natural frequencies of the frame of the printing machine. So the method is proved correct and available. Furthermore it can be concluded that the vibration of the frame determines the vibration of the cylinders.