A Note on a Longitudinal and Torsional Type of Ultrasonic Motor with two Stators

Abstract

This paper deals with an ultrasonic motor, which consist of one rotor and two stators. The main parts of each stator are one longitudinal and one torsional piezoceramic actuator, which are used to generate the desired elliptical orbit on the stator surface. For the purpose of a high efficiency, the longitudinal and the torsional resonant frequency should ideally coincide with the operational frequency. To match the resonant frequencies, two adjustable rings are added to the stators. The influence of the mass and the position of the rings on the first longitudinal and the first torsional eigenfrequency and their mode shapes is investigated. The experimental results fit very well with the theoretical predictions and show that the adjusting rings can be used to match the eigenfrequencies of the two mode shapes.

Research concerning ultrasonic chains with torsional vibrations for different industrial applications

“…A particular application of this principle is represented by an ultrasonic needle used for deep penetrations of bones [6]. It is also mentioned, although this is not the main subject of the paper, that longitudinaltorsional vibrations are applied on large scale for some time at ultrasonic motors [7,8,9]. Some constructive solutions regarding different shapes of transversal profile of helicoidal channels were studied to couple longitudinal and torsional vibrations within an ultrasonic chain that uses 1268 (2022) 012003 IOP Publishing doi:10.1088/1757-899X/1268/1/012003 2 Langevin transducers [10].…”