Abstract
This paper studies a kind of nine-bar linkage applied to mechanical forming presses including a five-bar linkage, a slider-crank four-bar linkage and a connecting link. First, it discusses the motion of the nine-bar linkage by kinematic analysis process. Then an approach of designing the nine-bar linkage is proposed by combining the synthesis of the linkage mechanism and the trial and error method to optimize the linkage for the ram cycle and the space requirements.