| 3D printing technology, also known as rapid prototyping, is an emerging technology. Among them, melt extrusion-based deposition modeling (FDM) rapid development of3D printing technology, with extensive molding materials, molding equipment requirements low, simple operation, and low environmental requirements, it relates to materials, machinery, electronics, software, etc. fields. Nozzle is one of the key components of the FDM-based3D printing, the mechanical structure of the complex, the motor speed and temperature stability is to ensure continuous and uniform spinning nozzle critical. Therefore, the motor-driven sprinklers and temperature control study has important significance.We found that the lack of previous FDM nozzle, based on traditional FDM nozzle design of its mechanical structure, effectively solves the problem of slippage and blockage cleanup FDM nozzle, in order to accurately control the stepper motor, stepper motor herein acceleration and deceleration control, to achieve5paragraphs S curve acceleration and deceleration. A finite element analysis model, provides the necessary basis for the temperature control parameters, Bang-Bang control and PID control and fuzzy control combine to get the important parameters temperature control, PC client management software is designed to achieve the data the real-time detection, storage and processing.This paper is divided into a total of four parts, the first chapter introduces the3D printing technology research and development situation at home and abroad, applications, application prospects, key technology; outlines the FDM working process, the mechanical structure and the traditional processing differences; elaborated3D printing difficulties in materials and equipment. FDM nozzle in terms of motor speed and temperature are higher, and discusses the basic PID control and fuzzy control theory, pointing out that the focus of this article. The second chapter introduces the working principle of3D printing technology, FDM sprinklers were on mechanical design, mechanical structure optimized to make more to meet the spinning nozzle FDM, temperature and operating requirements; calculated drive extrusion mechanism force, the motor drive circuit is designed FDM extrusion nozzle mechanism, FDM extrusion rate and the spinning nozzle directly affects the quality of the molding stability FDM nozzle, in order to accurately control the speed of the stepper motor, to avoid loss of synchronism, the use of acceleration and deceleration control, and stepper motor speed control experimentally measured to achieve a5paragraphs S acceleration and deceleration control. The third chapter established for the FDM nozzle preliminary thermal analysis finite element model to determine the initial conditions of finite element, geometry, material properties and boundary conditions, Simulation finite element simulation in SolidWorks environment, access to FDM nozzle temperature distribution, for subsequent to provide the necessary basis for the temperature control. To achieve a detailed analysis based on the PID control and fuzzy control for the FDM nozzle temperature which according to the requirements. Chapter IV built the FDM nozzle temperature tested hardware platform designed thermostat test software and PC interface for real-time monitoring of temperature and adjust the parameters, conducted experiments and fuzzy PID temperature control thermostat experiments.Experimental results show that:in the FDM nozzle, start the motor speed is60r/min, maximum operating speed of the motor600r/min, using5paragraphs S deceleration control is realized from the stepper motor stop control, the stepper motor to get an accurate control, effectively avoiding the step phenomenon. In the fuzzy heads of FDM temperature control accuracy of2℃or less,3%overshoot, settling time of105s (PID temperature control accuracy of1℃, the overshoot was10.95%, stable time for the273s), fuzzy control small overshoot, settling time is short, to achieve a stable control of the FDM nozzle temperatures. |
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