Static and dynamic characteristics of modified cymbal mechanism in micro punching system

This paper presents the development of a high speed micro punching system with modified cymbal mechanism. To realize the high speed micro punching, we introduced the hybrid system with a macro moving part and micro punching part. The macro moving part includes a ball screw, a linear guide and the micro step motor and micro punching part consists of PZT actuators and displacement amplification device with modified cymbal flexure hinge mechanism. The PZT actuator is capable of producing very large force, but they provide only limited displacements which are several micro meters. Thus the displacement amplification device is necessary to make those actuators more efficient and useful. For this purpose, a cymbal-type flexure hinge mechanism in series is proposed. The finite element method was used to design the flexure hinge mechanism and analyze the mode shape of the one. The displacement and mode shape error between the FEM results and experiments are within 10%. A considerable design effort has been focused on optimizing the flexure hinge to increase the output displacement and punching force.