纵扭复合型超声波电机的力传递模型

FORCE TRANSFERING MODEL OF HYBRID TRANSDUCER TYPE ULTRASONIC MOTOR

复合型超声波电机是各种超声波电机中最典型的低速大力矩电机,其定转子接触方式是断续面接触,这与行波型电机连续的若干点接触不同,也是实现大力矩的根本原因,因此分析其定转子的力传递模型很重要。该文先简单叙述了以往采用等效电路描述具有的问题,其次,通过电机轴向冲量守恒建立了定转子接触角与电机预压力和摩擦材料物理参数的关系,随后利用振动周期内周向电机负载和驱动力所作的功相同的原理,给出电机负载与定子纵 扭振动和转子参数的关系,并据此确定电机转子参数和预压力,研制的复合型超声波电机(直径80mm)的堵转力矩为13.2 N穖的大力矩,空转转速为12.5 r/min。初步形成了电机转子设计的理论基础。

Among all kinds of ultrasonic motor,the hybrid transducer type ultrasonic motor is typically low speed and high torque one. Its rotor and stator contact intermittently and the contact area always remains the same, which is the basic reason to realize high torque and differs from traveling wave type, in which the contact area moves with traveling wave. And so it is important to analyse force transfering model between the rotor and stator. First, the paper points out deficiency in previous equivalent-circuits. Next, based on momentum conservation in axial direction, the paper deduces the relation among rotor/stator contact angle, preload and physical parameters of friction material. And then based on the fact that the driving forces work equals to the circumferential load in a vibration cycle, the paper presents the relation among the load, the stators longitudinal and torsional vibration and the rotors parameters,and subsequently determines rotors parameters and preload. By these research, we have developed a megatorque hybrid transducer type ultrasonic motor with 13.2Nm in maximum torque, 80mm in diameter and 12.5 r/min in revolution speed and are initially forming the theory foundation of rotors design.