Research On The Elastic Clamping Device Of V-shape Linear Ultrasonic Motor

This project was granted by the project of the National Natural Science Foundation of China. (Contract No: 50735002).Besides the common characteristics of rotary ultrasonic motors such as small volume, light weight, fast response, low noise, not affected by electromagnetic interference,linear ultrasonic motor also possess the outstanding advantage of high displacement resolution. consequently, linear ultrasonic motor has wide application prospects in precision positioning fields.Elastic clamping device is responsible for the connection between stator and slider, and it is closely related to the motor's output performance.Stability,displacement resolution and output force are the three main factors which restrict the motor's development. The purpose of this project researches on elastic clamping device is to improve the three performance indicators.Generally speaking, the main contents and research results of this project are summarized as follows: The role of elastic clamping device was analyzed,and the existing problems of elastic clamping device were studied,on that basis the linear ultrasonic motor's ideal clamping model and the practical clamping model were put forward.Through comparison and analysis, three requirements which the elastic clamping device should meet were put forward. Limit the stator's redundant degree of freedom (DOF), facilitate loading pre-force,and provide appropriate elastic supportThe research uses the V-shape stator which was designed by precision driving laboratory Nanjing University of Aeronautics and Astronautics. According to the proposed requirements, three types of clamping schemes were designed. They were the clamping device based on flexible hinge, the clamping scheme based on double leaf-springs,and the clamping scheme based on three rollers.The motor's mechanical performance ,stability and displacement resolution were tested, and they were improved significantly. The elastic components which applied to linear ultrasonic motor were studied by experiment,and the methods which can improve the motor's performance were put forward.Generally speaking, the achievements of this research help shrink the development cycle of linear ultrasonic motor, and lay a foundation for the motor's practicalization and industrialization.