High-Speed, High-Precision Magnetic/Piezoelectric Hybrid Drive Actuator for Micro Electrical Discharge Machining

Abstract:

Electrical discharge machining (EDM) has the capability of machining all conductive materials regardless of hardness, and has the ability to deal with complex shapes. However, the speed and accuracy of conventional EDM are limited by probability and efficiency of the electrical discharges. To improve the machining speed and accuracy, we developed a 3-DOF controlled, high-speed, high-precision, magnetic/piezoelectric hybrid drive actuator. For the actuator, a voice coil motor type of magnetic bearing having a positioning stroke of a few millimeters is used to control the motion of an electrode in the thrust direction in order to speedily maintain a suitable distance from the workpiece. Moreover, two piezoelectric elements having high response speed and high precision are used to achieve the vibration of the electrode in the radial direction in order to immediately remove the debris between the electrode and the workpiece. The positioning performance of the actuator is evaluated through experiments, and the experimental results show that the actuator possesses a positioning resolution of 1μm, a bandwidth of 120Hz and a positioning stroke of 2mm in the thrust direction, and a positioning resolution of 0.05μm, a positioning stroke of 10μm at 1000Hz in the radial directions.

• Periodical: Advanced Materials Research (Volumes 941-944)
• Pages: 2112-2115
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.941-944.2112
• Online since: June 2014
• Authors: Xiao You Zhang, Kouki Uchiyama, Tomohiro Ishizuka
• Keywords: Actuator, Electrical Discharge Machining (EDM), Magnet, Piezoelectric Element

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