Design And Experimental Research Of Inertial Piezoelectric Vibration Feeder

Vibration feeder is a type of important equipment widely utilized in the automatic machining and automatic assembly system. Traditional vibration feeders are mainly driven by electromagnet, which has the deficiency such as large volume, heavy mass, complex structure and loud noise. In the later 1970s, Japanese argued that, compared with traditional electromagnetic feeder, piezoelectric feeder driven by piezoelectric bimorph stands out due to its simple structure, no heat, no magnet effect, and energy-saving and other advantages. Based on the research on piezoelectric vibration feeder in existence, inertial piezoelectric vibration feeder is designed and developed through the use of piezoelectric bimorph and inertial mass as the feeder's driven source. The feeder's dynamic/kinetic and vibration model is established and comprehensive tests are carried out.The paper consists of five chapters as follows:Chapter 1 IntroductionWith the increasing industrial automatization, vibration feeder has been widely used in the automatized production line. Electromagnetic feeders, piezoelectric vibration feeder and ultrasonic feeding devices are three common feeding mechanisms. The significance of the research on piezoelectric vibration feeders is described in this chapter.. The feeder's development both home and abroad is introduced and the problem to be solved is presented lastly. Chapter 2 Basic Theory about the Piezoelectric actuation technology Ppiezoelectric vibration feeder makes use of inverse piezoelectric effect . The piezoelectric ceramic is a key component of the piezoelectric feeder. The main parameters of piezoelectric ceramics'properties include electromechanically coupled coefficients K, mechanical quality factor Q m, dielectric constantε, elastic constant s and piezoelectric constant d. The piezoelectric ceramics'preparation method and the PZT piezoelectric ceramics'properties are presented. One of the four vibration modes of the piezoelectric vibrator, LE vibration mode, is adopted for the piezoelectric bimorph, with big displacements, high controllability and high access speed. The bimorph's deformation principle and variety are elaborated. The effect of the change of parameter factors influencing bimorph's properties is analyzed theoretically.Chapter 3 Structure Design and Theoretical Analysis of Inertial Piezoelectric Vibration FeederThe structure of piezoelectric vibration feeder is designed,its running principle is expounded. Every part of feeder is designed,including hopper,top plate, base plate,support leg,leaf spring and bimorph bob. The dynamic model of bimorph bob is established; the connections among empty-out time, parts movement and amplitude are analyzed. The vibration analysis is conducted on the feeder,the vibration model is simplied.Chapter 4 Experimental Research on Inertial Piezoelectric Vibration Feeder The inertial piezoelectric vibration feeder could be affected by various factors. Orthogonal experimental design is a convenient and feasible method to deal with the various factors. Basing on the orthogonal test's basic theory, the feeder's orthogonal experiment is designed to determine the optimal combination. The relations among voltage, frequency, amplitude and feeding rate are explored. The connections among piezoelectric bimorph, inertial masses, supporting spring strips, bottom feet and resonance frequency are fixed on by and large.Chapter 5 Conclusions and ExpectationThe main conclusions are arrived at, and the areas needing to be perfected in future and studied further are put forward in this chapter.