A Research On Ultrasonic Vibration-assisted Machining Based On Contactless Power Supply Technology

Ultrasonic vibration-assisted machining is a non-traditional machining process that combines traditional machining and ultrasonic vibration.It comprises of a tool mounted on a rotary spindle attached to a piezoelectric transducer to produce the rotary and ultrasonic motion.In ultrasonic vibration-assisted machines,the ultrasonic vibration power generated from the ultrasonic generator need to be transferred to the machine tool that rotating in a high speed.The conventional energy transfer method for ultrasonic vibration-assisted machining is via slip ring,where exists mechanical friction and has the potential risk of causing high-voltage discharge and electric sparks.Moreover the direct-contact electricity transmission cannot work on a spindle rotating in high speed,which affects the machining accuracy and working efficiency of ultrasonic vibration-assisted machining.Therefore a new and novel method of power transfer for ultrasonic vibration-assisted machining is in great need.Loosely coupled inductively power transfer(LCIPT)is a novel energy transfer technology that could achieve power transfer without physical contact.LCIPT owns many merits,such as reliability and minimum maintenance requirement.It is unaffected by dirt,dust,water or other chemicals and it is capable of working in high-speed rotation condition.LCIPT is widely used in aerospace,medical electronics and electric vehicle.Therefore the LCIPT technology might be a great choice for ultrasonic vibration-assisted machining.The main work of this paper is summarized as follows:1.This paper describes a novel application of LCIPT on ultrasonic vibration-assisted machining,which is building a contactless power transfer system,also named rotary transformer that could achieve the power transfer from the ultrasonic generator to the spindle in ultrasonic vibration-assisted machines.Principle of the rotary transformer is analyzed.Model of the rotary transformer is built,and the resonant compensation strategy of rotary transformer is designed.And the rotary transformer is simulated through Maxwell to validate the results of the model and make optimizations.2.Theoretic analysis of the ultrasonic horn for ultrasonic vibration-assisted machining.The ultrasonic horn is simulated by the finite element theory,and then the generatrix of the ultrasonic horn is optimized according to the simulation results to gain a better performance of the ultrasonic horn.3.Assembly and experiment of the ultrasonic vibration-assisted machining device.The assembly part includes connecting the ultrasonic generator,the ultrasonic transducer and the ultrasonic horn as well as designing the shell for the whole ultrasonic vibration system and the connecting device for the machine center.4.Experiments will be carried on for the ultrasonic vibration-assisted machining.The main contents of the experiments is to test the output of the machining tool,to see if the frequency and the amplitude of the vibration of the machining tool is sufficient for ultrasonic vibration-assisted machining...