A New Type of Piezoelectric Linear Motor: The Stator Design

Abstract

A new type of piezoelectric linear motor driven by bimorph actuator is developed. The stator fundamentally consists of a meander-line structure and a gear teeth mounted on the meander-line structure is focused in this article. The meander-line structure with bimorph actuators in a line driven by two sets of AC power with phase difference can generate traveling wave. The traveling wave is transferred to the carriage by the gear teeth, and thus forms a linear motor. Modeling of the meander-line structure is derived. Simulation by ANSYS for several different key parameters is presented. � Keywords: meander-line structure, bimorph, piezoelectric actuator I. INTRODUCTION In the recent decades, many researches on various types of piezoelectric motor have been investigated. Fundamentally, according to the vibration mode, piezoelectric motor can be categorized into single mode and multi-mode. Two main types, the rotary ultrasonic motor as a single mode and the linear piezoelectric motor as a double mode are popular seen and used in the industries. The former one is driven by traveling wave, and Sashida developed a first traveling-wave ultrasonic motor in 1982 (1). The latter one is driven by a combination of the longitudinal and bending vibration modes, and Tomikawa et al. developed a linear motor in 1992 (2). Regarding the traveling-wave type of ultrasonic motor, Ueha and Kurosawa developed an ultrasonic rotary motor in 1988. Piece to piece of piezoelectric ceramics connected with different (positive and negative) driving phases next to each other in a circle generate traveling wave, which moves the above rotor with an effective displacement (3). In 1990, Segawa et al. built a circular shape of ultrasonic motor with five positive and negative poles next to each other driven by two voltage resources with 90° phase difference. The stator