Design of a Dual-Resonance Excitation Langevin Piezoelectric Actuator Using Taguchi Method

For injection molding, knock-out pin will leave ejector marks on the parts of product. While making micro-structured components, the pin for normal ejector system is usually bigger than the micro-structured one. It would leave marks while part ejection process and it would even destroy the exterior of micro-structured components sometimes. In order to avoid this situation, this research is to design a Langevin transducer using the theory of Smooth Impact Drive Mechanism (SIDM) as a linear actuator. The dimensions of the Langevin piezoelectric actuator was determined using the Taguchi method to set the first and third minimum impedance frequency ratio at nearly 1:2. The mold equipped with the double layer Langevin transducer could demold the parts without knock-out pin in the plastic injection molding process.