Study On Dynamic Design Of Two-mass Vibratory Feeder

Two-mass vibratory feeder is widely used in metallurgy, coal, electric power,chemical, building materials, light industry and food industry in feeding equipment etc.But the production practice has showed the following shortcomings: high powerconsumption, unstable amplitude, low output, high noise, short service life etc. In addition,the traditional design is mostly using empirical data and safety coefficient design method,which can not accurately reveal the internal structure of the dynamic stress distribution;therefore it can not guarantee the product structure design is reasonable, which directlyaffect product performance and service life. Therefore, researching and manufacturingTwo-mass vibratory feeder by modern design method，upgrading the level of design,shortening the product development cycle and improving product reliability have becomeimportant research subjects. This dissertation has used virtual design, dynamic design,optimization design, finite element analysis, dynamic simulation and other modern designmethods to carry out research on dynamic design of two-mass vibratory feeder.On the bases of the study in working principle of the two-mass vibratory feeder andthe material motion in the trough, the formulas of the displacement, velocity andacceleration of the working face and the theoretical average velocity of the material motionare obtained. The principles and methods chosen for the proper process parameters for thetwo-mass vibratory feeder are summarized, and the Optimization Toolbox of MATLAB isused to get the best kinematic parameters for the small obliquity elliptical vibratory feeder,with the maximal conveying velocity and under the material throw condition.The dynamic model and four freedom degrees vibration equations of the two-massvibratory feeder are established. The method which solves the vibration equations is putforward. According to the analysis of vibration equations, the reason that results in forwardand backward swing of the two-mass vibratory feeder is that exciting force doesn’t passthrough the centroid. Based on that, the approaches to prevent the feeder from swinging arealso put forward. Calculation of the kinetic parameters of two-mass vibratory feeder, forthe finite element model is created and dynamics simulation study provides basic data.Based on Visual Basic6.0, the paper does secondary development for SolidWorks.Establishing interactive interface, completing different parameters of the model updated byVisual Basic programming, automatically saving every parts and assembly.Three-dimensional solid model is automatically converted to the two drawings for directlyused in the production. Finally integrating above function the paper creates a virtual design system as user interface, thus shorten the product development cycle, save manufacturingcost, and improve design quality.Using3D CAD software SolidWorks, the finite element analysis software ANSYS,multi body dynamic simulation software MSC.ADAMS joint simulation technology, andestablished a two-mass vibratory feeder rigid-flexible virtual prototype model, the buildingof two-mass vibratory feeder rigid-flexible virtual prototype model. Using the establishedmodel of virtual prototype dynamics simulation analysis is based on the two-massvibratory feeder to get the kinematics and kinetic parameters, which are the main vibrationspring and vibration isolation spring force curve and vibration direction angle curve andparameters. Simulation results, theoretical calculation and experimental results werecompared, the simulation result with the theoretical calculation and experimental resultsare in good design, which proves that two-mass vibratory feeder dynamic simulationmodel is correct. The simulation study also shows that during starting up and stoppingstage, feeder appears around the swing, but range is not big, the vibration isolation springbear larger impact load, prone to shear failure, the master vibration spring force is verysmall, the main failure patterns for the phase stability of fatigue failure; the averagetwo-mass vibratory feeder of vibrating direction angle of the simulation value is34.8°anddesign value of35°theory basically is the same, proved that the two-mass vibratory feederhas better production efficiency.The ANSYS software is used to analyze the unconstrained mode of the feeding trough,it has shown that the resonant of feeding trough does not appear on the rated workingfrequency, and the structure design of the feeder trough is reasonable. So the constrainedmodal analysis and harmonic analysis are conducted. It shows that the two-mass inertialvibratory feeder can conquer resonance, and reposeful starting and normal working can becarried out. Appling to ANSYS Workbench, the paper does fatigue analysis of mastervibration spring, a feeding trough body and other key vulnerable parts in this section,obtaining the parameter chart of the life, damaged and safety factor, analyzing therationality of the design of the structure, estimating their service life, finding the weaklinks, unsafe and easily damaged area to provide a basis for design optimization andproduction strength.No-load experiment research of the two-mass vibratory feeder is accomplished. Themotion tracks and vibration direction angles of every measuring point are obtained. Theexperimental and theoretical results are basically consistent. It proves that the dynamicanalysis is right. It is also shown that the working performance and dynamic characteristic of the feeder can meet the design aims. Through the unconstrained modal experiment studyon feeding trough, the natural frequency and vibration modes of feeding trough areobtained. The results, which are basically consistent with the theoretical results showingthe finite element model is reasonable.