Research Of Wheat Vibration Screen Based On Two Degree Of Freedom

Vibration screen is a kind of screening equipment for removing impurity according to the different size of particle material.The vibration screen is vibrated by external force and the material in sieve is dispersed,layered,filtered and transported to destination at the same time to achieve the effect of particle sorting.Vibration screen has been widely used in agricultural machinery,coal,mining,metallurgy,petroleum,chemical,construction,food,feed and other field.This paper has designed a kind of 2-DOF vibration screen to improve the material's uneven distribution in 1-DOF vibration screen and the vertical amplitude is not good.This paper provides a new way to solve the problem of slow flow of material in 1-DOF vibration screen and clogging of material.It has important practical significance and application value to establish the theory of 2-DOF vibration screen.This paper is supported by "Special Fund for Agro-scientific Research in the Public Interest"(201003077),and presents a kind of 2-DOF wheat vibration screen structure to solve the problem of 1-DOF vibration screen in actual production and life.The main research work includes:1.This paper analyzes displacement,velocity and acceleration of the sieve by taking the 2-DOF test platform as the research object.The moving trajectory and motion characteristics of the sieve are studied.The model was simplified and the motion parameters were analyzed through analyzing the displacement,velocity,acceleration and the force to the efficiency of the screen.The rationality of the design of 2-DOF vibration screen was confirm.It provides the basis for determining the size of 2-DOF vibration screen.2.The study of 2-DOF vibration screen based on the motion characteristics,dispersion,material surface layer and screening process,this paper further studies the material with each beat of the sieve and the material's beat frequency,then according to the mechanical principle and mechanical design theory,the optimal scheme is selected.This paper establish 2-DOF vibration screen three-dimensional model through the Inventor professional software,the assembly drawing,part drawing,test bench measurement and control system are provided,which is convenient for trial manufacture and test study.3.This paper establishes a model of 1-DOF vibration screen and 2-DOF vibration screen through ADAMS simulation software.Through the simulation analysis,we conclude the curves of screen surface inclination?the curves of horizontal displacement and acceleration?the curves of vertical displacement and acceleration from two different screens.The horizontal acceleration of 2-DOF vibration screen is larger than 1-DOF,in contrast,the vertical acceleration of 2-DOF vibration screen is less than 1-DOF.Through the analysis,we conclude that this design requirements is reasonable.This results provide a reference for optimization of the vibration screen.4.2-DOF vibration screen test bench has been built,and set up control system to complete the processing,assembling,debugging and testing.The test consists of two parts: the feeding test of material on 2-DOF vibration screen and the sieving performance test of 2-DOF vibration screen.Experimental results show: The feeding quantity of material is 1.2kg/min,and the primary and secondary order of the passing rate and the loss rate are rotating crank speed>translational crank speed>connecting rod length>translation eccentricity>rotation eccentricity.The optimal combination of factors is translational crank speed is 180r/min,rotating crank speed is 140r/min,connecting rod length is 170 mm,translation eccentricity is 20 mm,rotation eccentricity is 8mm.This experimental result verify the above theoretical analysis and ADAMS simulation result.