The Research On The Mechanism And The Extrusion Of Fused Deposition Modeling Ripid Prototyping Machine

Fused rapid prototyping technology has important research value, because of its extremely wide range of application. So it will be a tendency to explore a mature fused deposition model ing(FDM) rapid prototyping equipment, and make it commercialized. By using a Rostock-kossel fused rapid prototyping machine purchased from abroad, we have explored and developed the rapid prototyping equipment in some details, which are beneficial for people to know more about the rapid prototyping equipment,and to develop the fused rapid prototyping technology faster, and to popularize commercialized rapid prototyping equipment more easily. This paper is mainly researching and analyzing the parallel arm mechanisms of rapid prototyping equipment, and the process of material extrusion in screw nozzle.The main research content is as follows:Firstly, conclude the main performance parameters which affect FDM printer device mechanism, compare different kinds of FDM rapid prototyping equipment, design the overall mechanical system of our FDM printer device.Secondly, the paper introduces the parallel mechanism configuration of delta printer device and calculates its degree of freedom. We learned that it has three degrees of freedom of movement and has not rotational degree of freedom from experiments. Based on this evidence, we established position equations of the delta parallel mechanisms, then inferred both the positive and inverse solution of the position equations. According to the above equations, we determined the working space of delta parallel structures by using faster polar coordinate searching method of MATLAB software, and analyzed the discipline of which the mechanical path length, equivalent radius, the length of connecting rod,the limit angle of hinge might work on its workspace by using the measure of section.Lastly, the paper elaborates the material extrusion process of fused rapid prototyping machine. We divided them into three parts based on the diverse status of materials in different regions:feeding part, melted part, fused part. About feeding part, we analyzed the pressure, velocity and temperature of materials and computed the length of solid conveying section. About melted part, we simplified the process, set up models by ultilizing solid-liquid mass balance and the heat balance of solid-liquid phase interface, and eventually made a model simulation by using Fluent software to analyze the effects which the mechanical size might have on the simulation process. About fused part,we analyzed the flow distribution and velocity field and built models, then did simulation experiments using Fluent software. The paper presents a velocity and pressure chart gained from Fluent calculation, from which we can analyze the rheological property of materials in the fused period.