Linear Piezoelectric Stepping Motor with Broad Operating Frequency

The existing resonant linear piezoelectric motors must operate with high working voltage in resonant condition, resulting in their narrow operating frequency range and poor running stability. Here, with the large displacement output characteristics of piezoelectric stacks, the trajectory at the drive foot of stator is firstly produced with two space quadrature piezoelectric actuators excited by sawtooth wave and square wave. Secondly, the friction drive principle of motor is used to analyze the working mechanisms of the continuous stepping motion. Finally, the motor prototype is designed and experiments are carried out. The experimental result shows that the motor can stably operate within the scope of 350 Hz to 750 Hz. When the excitation voltage is 30 V and pre-load is 3 N or 10 N, the lateral amplitude of the drive foot is approximately 4 μm and the stable average interval ranges from 3.1 μm to 3.2 μm with the error rate of 5%-7.5%.