Piezoelectric linear motor using resonant-type clamping based on harmonic vibration synthesis

A piezoelectric linear motor (PLM), which has a mechanism based on synchronized switching control, is composed mainly of a driving unit and a clamping unit. A resonant-type clamping (RTC) unit is developed to increase the working frequency of the motor. The developed RTC unit is a three-layer tuning fork structure with ten pieces of single-layer piezoelectric sheets as driving elements. The RTC unit was designed to have a resonant frequency ratio of 1:3:5 by deliberate design of the lengths and widths of each layer. A resonant-type quasi-square-shaped mechanical wave was obtained combined with the three vibration modes of those layers. A PLM prototype that utilized the developed RTC unit was fabricated and tested. The moving speed of the slider can reach up to 78.3 mm/s at a driving voltage of 240 Vp–p.