Tracking And Identification Of Melt Front Position By Real Time Signal Processing

In response to the increasing miniaturization of consumer and medical products, and the corresponding need for micro/miniature parts, a miniature plastic injection molding machine which with precision down to below milligrams range (<0.05mg) is in the process of developing. Through the studies, it is found that an active mold design that links with the control system of the injection machine will provide an answer to the required below milligram precision and utilize the high precision of the machine. In the injection process, in order to control the speed and time accurately, the pressure signature of the front of the melt liquid should be investigated when it passes through the nozzle of the injection machine.This paper is to control the push speed of injection moulding machine's plunger via the mastery of the time when the melt front passes through the nozzle of the machine, so that the quality of the products can be insured. To achieve the goal, this paper firstly designed the experimental platform of the system, which uses AutoCAD to accomplish it. In order to investigate the pressure signature when doing the experiment, the organic-glass is used to form the part of the injection unit so that the experiment datum can be collected more conveniently. Then the mathematical model is set up for the experiment object, the proper filter algorithm is chosen and it uses MATLAB to simulate the algorithm. Because the injection process in micro-injection procedure is very fast, the real-time algorithm is selected to satisfy this demand. The last results of the experiment indicate that, the algorithm that used in this paper can satisfy the experiments' requests.The paper studied the melt front position of the injection moulding machine when it is working. In the studying, the experiment platform is designed, the target tracking algorithm is presented and the test model is simulated. Last, the result of the experiments show the algorithm can achieve the target. It can solve the problems in the controlling of the plunger's push speed of the injection moulding machine.