Miniaturization of the Quasi-Traveling Wave Ultrasonic Linear Motor Using a Ring Type Rectangular Vibrator

Abstract

Ultrasonic linear motor, Piezoelectricity, Rectangular vibrator, Traveling wave Abstract. With the aim of realizing quasi-traveling wave drive in ultrasonic linear micro motors, a novel quasi-traveling wave ultrasonic linear motor using a ring type rectangular vibrator with the sizes of 39mm×6mm×12.7mm is proposed. The quasi-traveling wave is excited and propagates along the ring type rectangular vibrator depending on the superposition of two orthogonal flexural-vibration modes with a spatial phase shift of 90 degrees. 7 piezoelectric ceramic elements are used to excite two working modes of the vibrator. The vibrator structure was designed and eigenfrequency degeneration was realized by Finite Element Analysis (FEA) method. The modal test shows that the design scheme was tenable. The excitation and propagation of quasi-traveling wave were proved by laser vibration test. The trial motor gave a maximum driving velocity of 162.5mm/s and a maximum load of 8.5N, while the excitation frequency was 66 KHz and voltage was 160Vpp.