Title : 
Piezoelectric ultrasonic motor using longitudinal-torsional composite vibration of a cylindrical resonator
         
        
            Author : 
Ohnishi, O. ; Myohga, O. ; Uchikawa, T. ; Tamegai, M. ; Inoue, T. ; Takahashi, S.
         
        
            Author_Institution : 
NEC Corp., Kawasaki, Japan
         
        
        
        
        
            Abstract : 
A piezoelectric ultrasonic motor, which uses longitudinal and torsional composite vibration of a cylindrical resonator, was investigated. It was found that the resonant frequencies for longitudinal mode and torsional mode could coincide with each other in the cylindrical resonator, according to finite element analysis and experimental measurement. The motor using both resonant vibrations showed good performance. The 20-mm-diameter motor exhibited a 4 kgf-cm maximum torque, a 450-r.p.m maximum rotational speed, and a 40% maximum efficiency
         
        
            Keywords : 
electric motors; piezoelectric devices; small electric machines; ultrasonic devices; cylindrical resonator; finite element analysis; longitudinal mode; piezoelectric ultrasonic motor; torsional composite vibration; torsional mode; Ceramics; Couplings; Finite element methods; Piezoelectric polarization; Pressing; Resonant frequency; Rotors; Stators; Torque; Vibrations;
         
        
        
        
            Conference_Titel : 
Ultrasonics Symposium, 1989. Proceedings., IEEE 1989
         
        
            Conference_Location : 
Montreal, Que.
         
        
        
            DOI : 
10.1109/ULTSYM.1989.67085