| Ultrasonic Motor(USM)is a new type of motor that has been developed quickly in recent years at home and abroad. It's a driving device that is driven by ultrasonic vibration that is then delivered by rotor through the friction between stator and rotor. This kind of vibration can be changed into continuous revolution or linear move; It's the way USM works. One unique characteristic of USM is that no electromagnetic coils are used in them, instead of the interference of coils, the PZT's effect is used as the energy to produce ultrasonic vibration, which is amplified and changed into rotor's movement. So you can see stator (made of PZT) replaces the millions of electromagnetic motor, such as high torque and low speed, high-energy volume ratio, short response time, no interference of electromagnetism, etc. It has prospect in the field of aviation, precise instrument and robot, etc. Moreover, USM itself doesn't produce magnetic field, but high torque and low speed, high-energy volume ratio. It costs less and has been used in the camera. It can work at the speed of several rpm to several hundred rpm, no need of the gears to change its speed. For this, many problems resulted from gears, like the problems of big noise and low efficiency, can be avoided. Now we regard USM as a new driving device which not only makes a breakthrough of the traditional mechanical motor, but also supplements and enriches our transfer tools.Ultrasonic motor is a typical electromechanical unifinication product. It is concerned with physics, function material, tribology, contact mechanics, fluctuation theory, function material, workmanship electronic science and calculation science and experiment technology etc. It is a new interdisciplinary high technology, leaving a lot of theoretical problems unclear. Compared with electromagnetic motor, it is lack of design experience, not established systematic design theory and design method.Importance has been attached on the Longitudinal-Torsional ultrasonic motor for its great advantages in easy control, high power output, high torque and low speed, high-energy volume ratio, etc. In this paper, the driving mechanism, friction contact, mathematical model, ultrasonic transducer design and experiment is studied systematically and theoretically.1. The ellipse movement of motor stator surface and driving mechanism are analyzed systematically and theoretically. Through establishing the mathematics model of stator surface particle ellipse movement, we draw a conclusion that stator surface ellipse movement produced by ultrasonic and friction is the prerequisite condition of motor drive, that phase difference, the amplitude ATand that ALdecide the formation of ellipse sport andthe rotor's location, all these directly decide ultrasonic motor's efficiency and the bearing capacity. Thus it is important to controlsuitable phrase difference and the amplitude AT >. AL.2. The pre-pressure , the mechanism of Longitudinal-Torsional ultrasonic transducer' s output effect and the effect of friction material on motor performance are analyzed , the criterion of friction material is presented.3. A two-dimension elastic contact model is used for establishing the friction drive between the rotor and the stator of the motor. Base on the ultrasonic motor' s stator and rotor ideal linear contact, an assumption is made, and an electrical equivalent circuit is used to estimate the interaction between the electrical and mechanical parts of the stator.4. Having made use of the motor that established, and analyzed Longitudinal-Torsional transducer' s resonance frequency equation of vertical vibration and torsion vibration under the condition of being stimulated alone, we have studied Longitudinal-Torsional transducer' s frequency annexing. Through contrasting with some kinds of transducer design methods, we have determined the way of design Longitudinal-Torsional transducer. Using the method of value analysis, we have analyzedLongitudinal-Torsional ultrasonic motor and the influence of ultrasonic motor reso...
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