A new design method for single DOF mechanical presses with variable speeds and length-adjustable driving links

This paper proposes a new design method for obtaining or improving the desired output motion characteristics of single-degree-of-freedom mechanical presses by appropriate design of the speed trajectory and length of the adjustable driving links. This approach adds a ternary link to the original mechanism. The ternary link is adjacent to the driving link, roller link, and connecting link, making use of a sliding pair, revolute pair, and a second revolute pair, respectively. The roller link is adjacent to the ternary link and fixed link by a revolute pair and a rolling pair. It is guided by a specially designed slot in the fixed link while the driving link is driven by a servomotor with a specific speed trajectory. A Bezier curve is used to design the input speed trajectory and the contour of the slot. Examples are given to demonstrate the feasibility of this work.