Characteristics of multilayer piezoelectric actuator made of high Q material for application to ultrasonic linear motor

Recently, we have developed a low voltage drive ultrasonic linear motor using a L-1-F-2 double mode stator vibrator I made of multilayer piezoelectric actuators (MPAs). However, when the linear motor was continuously driven, the temperature rise of the stator vibrator was over 20degreesC. This is mainly because the MPA used by us is made of a low Q piezoelectric material (soft material MPA), which is usually applied due to its large piezoelectric coupling coefficient. Therefore, in order to reduce heat generation of the MPA, we tried to apply a MPA made of high Q piezoelectric material (hard material MPA), which has been little applied to date. As a result, it is clarified that the temperature rise of the hard material MPA is far less. than that of a soft material MPA and therefore the temperature rise of the stator vibrator using the hard material MPA is also far less than that of the stator vibrator using a soft material MPA Additionally, in this paper, it is reported that performances of the ultrasonic linear motor composed of hard material MPA are superior in practical application.