Ultrasonic motor and electronic apparatus with ultrasonic motor

摘要

In frequency-admittance characteristics of a stator, the frequency with a resonance point at which the admittance value is minimum and that with a resonance point adjacent thereto are set to be apart from each other and thereby an ultrasonic motor having less variations and high output power is provided. In addition, an ultrasonic motor is provided in which support and pressing structures and a conduction structure are improved for the purpose of achieving a size reduction. Two elastic bodies are disposed in upper and lower positions and have grooves at their respective surfaces. These grooves are provided at regions corresponding to nodes of standing waves that are stress concentration zones so as to cause large torsional displacement. The grooves are provided in places other than the upper and lower surfaces of the elastic members. In addition, these grooves have a smaller angle than 90 degrees.