STUDIES ON CONSTRUCTIONS AND CHARACTERISTICS OF PIEZOELECTRIC ACTUATORS

1.超声波电机首先，系统地研究了超声波电机的几种结构，通过考虑用于形成椭圆位移运动的模式组合来给出转子的旋转，发现超声波电机可以分为三类(技术报告发表：5)。其次，通过样机电机的实验研究了具体电机的特性。也就是说，(1)在使用弯曲-弯曲多模振子的电机中，利用圆盘或环板的非轴对称振动模式来实现轻载型和重载型的薄型电机。此外，还对这些振动模式进行了详细的分析，明确了将其应用于超声波电机的一些设计条件。(2)在采用纵弯多模振子的电机中，主要可以实现一种新型的平板型直线电机。(3)在采用纵扭振动模式的电机中，利用多模振子可以实现1.0-3.0 Kg.cm重载的杆状电机，并且可以将纵向振动的单谐振子和扭转振动的单谐振子结合在一起获得轻载电机(技术报告：8)。(1)研究了一种线性自移动驱动器和(2)一种纸张或卡片转发装置。前者采用细杆型纵弯B8多模振子和(R，1)-((1，1))型环板振子实现机器人快速响应装置(技术报告：3)。在后者中，可以开发新的供纸器和预付费P卡读卡器(报告：2)。3.研究了用于时钟应用的小位移器件(1)高速工作的输入电压波形和(2)角位移的一种新的精确控制方法。

1. Ultrasonic Motors First of all, some constructions of an ultrasonic motor were investigated systematically by considering mode combinations used for formation of an elliptic motion of displacement to give the revolution of rotor, and it is found that the motors could be classified into three groups (Technical reports published: 5). Next, the concrete motor characteristics could be investigated through experiments of prototype motors. That is, (1) in the motors using flexural-flexural multi-mode vibrators, non- axisymmetric vibration modes of a disk or an annular plate were used to achieve the thin motors of light load type, and of heavy load type. Moreover, detailed analyses of these vibration modes were done and some design conditions for its application to an ultrasonic motor were made clear.(Technical reports: 16). (2) In the motors using longitudinal- flexural multi-mode vibrators, a new flat-type linear motor could be achieved mainly.(3) In the motors using longitudinal-torsional vibration modes, a rod-type motor for a heavy load of 1.0 - 3.0 Kg.cm could be achieved using the multi-mode vibrators, and moreover the motor for a light load could be obtained combining a single resonance mode vibrator of longitudinal vibration and one of torsional vibration (Technical reports: 8) 2. Linearly Self-Moving Devices As for the devices, (1) a linearly self-moving actuator and (2) a paper or card forwarding device were investigated. In the former, the longitudinal Ll-bending B8 multi-mode vibrator of thin bar type and the (R,1)-((1,1)) mode annular plate vibrator were used to achieve the robot device of quick response (Technical reports:3). In the latter, new devices for a paper feeder and a prepaid p card reader could be developed (Reports: 2). 3. Small Displacement Devices n an (1) Input voltage wave form for high speed operation and (2) a new precise control method of angular displacement were investigated to be utilized in the clock application.