Abstract: Stacking blank in stamping machine was studied and a blank dispersing mechanism using springs hanged above the stacking blank to disperse was developed. The model of the collision between the blank and the spring was established through the mechanical analysis. Based on the collision model, the optimized model for selecting spring was established, and on the basis of the parameters of a stamping machine, the SUMT was used to numerically calculate the optimized model and the optimum parameters of the spring which was used in the dispersing mechanism were obtained. The developed blank dispersing mechanism was proved to work well through experiment.