Design And Experimental Analysis Of Elliptical Ultrasonic Vibration Boring Device

As a new type of processing technology,elliptical ultrasonic vibration cutting technology has widely been concerned by scholars at home and abroad,for its advantages of reducing cutting force,prolonging tool service life,lowering cutting temperature,improving the surface quality and precision of processed workpieces,and improving chip evacuation.At the same time,the blade tip will not be subject to alternating tension and compression stress in the elliptical ultrasonic vibration cutting process,which can effectively reduce the occurrence of tool chipping.In addition,the flank face is detached from the machined surface in the stage that the knife and the workpiece separates,which contributes to improve the surface quality.Therefore,elliptical ultrasonic vibration cutting will theoretically improve and perfect linear ultrasonic vibration cutting.It is of great practical significance to design a reliable and efficient elliptical vibration cutting device.There are two ways to achieve single-excited elliptical ultrasonic vibration cutting:composite transducer and composite horn.This paper adopts the composite horn to transform the single longitudinal vibration output from the piezoelectric transducer into two kinds of composite vibration modes.It will realize elliptical vibration cutting at the end of the composite horn.At the same time,the composite horn and transducer are designed by calculating some parameters in theory.This paper combines theoretical design calculation,finite element simulation and experimental verification.Through the modal analysis of the composite horn,the natural frequency and mode shape are obtained which verifies the correctness of the relevant design theory.Through transient structural dynamics analysis,the trajectory of the tip of the composite horn is obtained,indicating that it can achieve elliptical vibration trajectory and verifying the correctness of the theoretical design.In addition,when the same external force is applied at the tool tip,the static analysis of two groups of composite ultrasonic oscillators shows that the maximum deformation occurs at the tool,but the maximum deformation of the longitudinal torsional ultrasonic oscillator is relatively small.The structure of piezoelectric transducer and mechanical system of the elliptical ultrasonic vibration boring device is designed.Through the design of the mechanical system,it is easy to connect the elliptical vibratory boring system and the boring machine,realizing elliptical ultrasonic vibration machining on the boring machine.At the same time,the impedance matching test to the ultrasonic oscillator is carried out by using the impedance tester.The experimental results show that the relevant design theory is correct.