Abstract:The working principle and advantages and weaknesses of traditional crank-slide mechanism used by the turret punch presses were analyzed briefly. The principle and advantages of knuckle mechanism were elaborated. Based on the background of application research of high-speed turret punch presses with 20 kN nominal pressure, 25 mm slide stroke, 4 mm slide block nominal pressure stroke, three different kinds of knuckle mechanisms were designed, and their kinematics models were built respectively. Then each structure size for the three different kinds of working mechanisms was gotten respectively through the optimization by computer, with 25 mm slide stroke as a condition of constraints and by the optimal aim of achieving minimum of their max slide velocity in their 4mm slide block nominal pressure stroke. And then their 3D structural models were built up, and their different parameters were analyzed and compared including the slide displacement, velocity and slide acceleration, and so on. The analysis results show that the synthetic performance of the “link curve” type of six bar linkage among these three kinds is the best.