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 horn.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.
A double cylinders type traveling wave ultrasonic motor using composite transducer was proposed.The proposed stator contained two cylinders and one composite transducer,and the transducer located on the outer surfaces of cylinders.The composite transducer included two exponential horns located on leading ends,and the horns insected with the cylinders at tip ends.Two degenerated flexural vibration modes spatially and temporally orthogonal to each other were excited in each cylinder by the composite transducer.In this new design,a single transducer could excite two flexural traveling waves in the cylinders.Thus,elliptical motions were achieved at the particles on the teeth.The working principle of the proposed motor was analyzed.The cylinder and transducer were designed with FEM.The resonant frequencies of two vibration modals of the stator were tuned to be the same,and the motion trajectories of nodes on the teeth were analyzed.Transient analysis results show that the motion trajectories of teeth are ellipses.The results of this paper can guide the development of this new type of ultrasonic motor.
