中文摘要：

研制了一种新型金属管状弯曲旋转超声电机，该电机的定子由一个具有12个棱面的金属管和粘贴其上的PZT片组成，其尺寸为外径够42mm、内径够34mm、长44mm。当电机运行时，在定子端面圆周上激发出3个波长的行波，定子以3个波峰同时与转子接触。试验结果表明，电机的工作频率为29．9kHz。在激励电压峰-峰值为250V，预压力为7N时，电机的空载转速为280r／min，堵转转矩为62N·mm，与同尺寸的采用4个激振区的弯曲旋转超声电机相比分别提高了40%和122％。

英文摘要：

A novel bending rotation ultrasonic motor is developed. The stator of the motor composes of a metal tube with twelve arrises and PZT pieces stuck to the metal tube. The sizes of the stator are 42 mm in outside diameter, 34 mm in inside diameter and 44 mm in length. When the motor operates, a traveling wave with three wavelengths is excited on the stator surface. The stator is in contact with rotor in three tiny areas. The experimental resuits show that the resonant frequency of the motor is 29. 9 kHz. When peak-peak value of exciting voltage is 250 V and pre-load is 7 N, the maximum angular speed is 280 r/min and the stalling torque is 62 N · mm. Compared with the same dimension motor using 4 exciting areas, the maximum angular speed and stalling torque are increased 40% and 122% respectively.