The Research Of A Rotary Ultrasonic Vibration System And Power Technology

With the growing demand for the processing of hard-brittle materials, carbon fiber and alloy materials, series of challenges have been brought forward to the mechanical manufacturing technology. The rotary ultrasonic machining have been proven to be an effective method for the processing of these materials, but the machining theory has yet to be established, especially on some key issues. For the traditional rotary ultrasonic machining, the power is supplied by brush, thus the rotational speed is limited.. Some others use brush-less rotary tool, but the energy transfer efficiency and transfer capacity are low.Based on the consulting a large number of relevant literature, this paper analyzed and compared the structures of existing rotary ultrasonic machining technologies, and reveals the lacks of the power supply methods using brush. n order to solve the above-mentioned problems, a inductive power transfer method is proposed. The basic mechanism of the inductive power supply technology is analyzed. Moreover, frequency tracking and intelligent control strategies are studied in detail, The studies in this paper include the following aspects:1) The transducer and tools (bar and cup-shape) are designed and developed, which are used later in rotary ultrasonic machining. The impedance characteristics, temperature characteristics, Multi-resonant frequency characteristics and assembly procedure of the ultrasonic vibrator are studied. Modal analysis and harmonious response analysis have been carried out using ANSYS software. The finite element simulation results are found close to the experimental results.2) This paper presents the principle of induction power supply technology. The ultrasonic machining system as well as the structure of the rotating transformer is designed. The characteristics of the rotary transformer made of twisted wire and copper foil are compared. The mutual induction model and the leakage induction models of the rotary transformer are established. The design process of the rotary transformer is presented in detail.3) Considering rotary transformer matching technology and comparing multiple matching methods, the series inductance matching and LC matching are simulated by Multisim software. Considering the effect of the load size on ultrasonic machining, the influential elements of the vibrator on load capacity is analyzed. By adding nonlinear variable of the transducer loading, the mathematical model of the transducer is improved. It provides a basis for the design and control of the transducer.4) Compared the self-excitation and separately excited characteristics of ultrasonic power, the digital ultrasonic power is designed and developed with composite frequency tracking of processing. Then the frequency scanning, power regulation and frequency tracking methods are verified.5) Based on adjusted matching inductance and scanning frequency technology, the adaptive control methods minimizing phase difference are designed, which realized automatic recognition of different transducer and the tools. The method which determines the best working condition is designed. The algorithm which compound of maxim μm current method and phase tracking are proposed.6) Considering the vibrator experimental data, we built the ultrasonic vibrator driven system hammer stein nonlinear model by PSO algorithm which driving frequency is the input, amplitude of the vibrator is output. Ultrasonic vibrator nonlinear multi-step predictive self-tuning control strategy and controller parameter setting methods are designed. The results show that the proposed control strategy is effective and robust.7) The examinations of material (such as glass and ceramic) drilling and grinding based on the research of the five axis rotary ultrasonic machine are made. And the processing control regular from comparisons of ultrasonic machining is summarizedIn this paper, some key techniques in the rotary ultrasonic machining are studied. The rotary ultrasonic machining using induction power supply device has the merits of high speed, simple structure and high efficiency energy transfer. It can automatically identify different tool, quickly find the resonant frequency and frequency tracking. As a result, the rotary ultrasonic machining of inductive power supply device has not only theoretical meaning, but also a good application prospect.