Actuating mechanism and design of a T-type linear ultrasonic motor

To take advantage of merits of higher output-power and efficiency of bolt-clamped transducer, a T-type linear ultrasonic motor was proposed in this paper. The proposed motor contained a horizontal transducer and a vertical transducer. The horizontal transducer included two exponential shape horns, and the vertical transducer contained one exponential shape hom. And the horns intersected at tip ends where a driving foot was located. The longitudinal vibrations of transducers were excited by the stretching vibration of PZT ceramics. Longitudinal vibrations were superimposed in the motor and generated elliptical trajectory at the driving foot. The actuating mechanism of the proposed motor was analyzed. The two working modals of the motor were gained with FEM. The resonant frequencies of two working modals were degenerated by adjusting the structural parameters. The motion trajectory of nodes on the driving foot was gained by transient analysis. The vibration amplitude of node on the driving foot indicates that the proposed motor has potential good output characteristics. The results verify the feasibility of the proposed design and provide instructions for the development of the new ultrasonic motor.