Injection Molding Machine Control Research Articles

Time series data for process monitoring in injection molding: a quantitative study of the benefits of a high sampling rate

Abstract Process monitoring systems are playing an increasingly important role in reducing production capacity losses in injection molding. Process monitoring and optimization systems are mostly based on processing data of injection molding machine control systems. These data consist of scalar data and time series. This paper introduces a novel approach to modelling injection molding processes using only time series data and evaluates the quantitative influences of varying sampling times on calculation of integral values and model quality. On the basis of the first experiment, it is shown that the sampling rates of these time series have a large influence on information which can be derived from this data (e.g. injection work). These findings provide an assessment of whether the effort is justified for the respective requirements on the accuracy of the injection work and other parameters derived from the time series. In the second experiment, a model is presented which uses only the injection flow and injection pressure profile as input and achieves high coefficients of determination for the prediction of the part weight, despite the absence of mold sensor data and scalar data. It is shown that higher sampling rates of time series results in higher prediction quality of these models. This improves the understanding of the data needed for high quality machine learning models of injection molding processes and enable users to estimate a lower bound for the sample rates of time series for their use cases.

Robust parameter search for IC tray injection molding using regrind resin

Abstract Quality consistency is essential in maximizing the productivity rate of the injection molding process and minimizing the production cost. The quality consistency problem is particularly acute in the case of injection molding processes performed using regrind resin, for which the rheological properties are less uniform and more unpredictable than those of virgin material. Accordingly, the present study proposes a two-stage approach for optimizing the injection molding process parameters in such a way as to achieve a consistent molding quality over repeated injection molding cycles. In the first stage, the values of the injection speed/pressure, velocity-to-pressure (V/P) switchover point, and packing pressure are individually determined based on an inspection of the cavity pressure profile and machine parameters provided by the injection molding machine controller. In the second stage, a robust parametric search method based on a first-order regression model is employed to determine the optimal combination of the process parameter settings. Using an Integrated Circuit (IC) tray fabricated from regrind resin for illustration purposes, the results confirm that the proposed method overcomes the problem of small variations in the melt quality and therefore provides an effective technique for improving the yield rate and quality of the continuous mass production.

The Design of the Injection Molding Machine Control System Based on PLC Controller

Control system of the Plastic injection molding machine formed by electric relays and switching valves has many shortcomings, such as complexity wiring, low control accuracy, inconvenience maintenance and lack of flexibility, using the simulation assessment of the actual application method, this paper designs the injection molding machine control systems based on PLC controller, the new control system is composed by PLC, inverter, sensors and other components, with the help of PID control, which according to the given screw barrel temperature deviation value and measured value, automatically adjust and stabilize of the entire control system. Simulation experimental results show this new control system can achieve better performance is effective, which will decrease energy consumption of the stabilization system; the research achievements have certain theoretical and practical value to the design of injection molding machine control system.

Heat Pipe Cooling Scheme Analysis of Injection Molding Machine Controller

In the long run, the problem of high temperature has been existed in a companys injection molding machine controller. In order to solve the heat dissipation problem, two kinds of heat pipe heat dissipation schemes are designed, CFD software ICEPAK is used in the report to make a numerical simulation as well as a simulation analysis of the Heat pipe cooling scheme. By comparing two kinds of cooling mode heat pipe cooling effect and structure process, Vertical-type heat pipe cooling solution that meets the cooling requirements and makes heat-sensitive components stay away from high-temperature, furthermore heat pipe processing technology is relatively simple.

Application of LABVIEW in the Experiments of Temperature Acquisition

In the long run, the problem of high temperature has been existed in a companys injection molding machine controller. CFD software ICEPAK is used in the report to make a numerical simulation as well as a simulation analysis of the injection molding machine controller and get the temperature contours picture, and then LABVIEW software is used to measure temperature variation with making program. The results show that: it confirmed the correctness of the simulation of software ICEPAK under the allowed error, it also confirmed that the cooling effect of the products of the company is not very good, furthermore it provided the foundation for the company to improve product. The attempt of applying ICEPAK Software and LABVIEW in the electronic equipment to optimize design is made.

Fan Cooling Scheme Analysis of the Injection Molding Machine Controller

In the long run, the problem of high temperature has been existed in a companys injection molding machine controller. In order to solve the problem of heat dissipation, a kind of fan cooling scheme has been designed according to structure characteristic of the controller, CFD software ICEPAK is used in the report to make a numerical simulation as well as a simulation analysis for fan cooling scheme and the original scheme, By comparing cooling effects of two cooling schemes, the fan cooling scheme can not only meet the cooling requirements, but also the structure is relatively simple. It solves the problem of high temperature of the injection molding machine controller, furthermore it provided the foundation for the company to improve product.

Based on Vector Control of All-Electric Injection Molding Machine Control System Design

According to the all-electric injection molding machine control system requirements, the vector control applied to the permanent magnet synchronous motor control, we propose a fully electric injection molding machine control system design, through analysis and research that can further improve the program precise all-electric injection molding machine control, its stability, high reliability, to better meet the all-electric injection molding machine of precision and stability requirements.

Overall Control System for Injection Molding Process

Abstract A multi-layer injection molding machine control system is proposed in this paper. The first layer, an advanced process parameter control layer, provides accurate and robust control of key process variables. The second layer consists of two modules, a profile setting layer determining the shapes of set-point profiles for the key process variables, to achieve an evenly distributed part quality along the flow directions; and a process fault detection and diagnoses system monitoring the operation of injection molding process. The third layer, a quality control layer, consists of a quantitative quality prediction model and a quality controller. This final layer provides a mechanism for closed-loop control of certain part quality. The related work that has been conducted on these three layers is discussed extensively in this paper, and the future work is introduced as well.

Enhanced Reliability of Mold Close and Open Control in Injection Molding Machine through Fuzzy Algorithm

Injection Molding Machine (IMM) has been widely used for the mass production of a plastic product. With the development of the relative technique, various injection molding techniques have been developed and we could get more precise plastic product. In this paper, we present the system reliability of an IMM subject to a controller. The controller of an IMM is an important factor in the injection molding and this controller has direct influence on the quality of a plastic product. Presently, the mold close and open control method of a toggle type IMM is openloop control. Open-loop method is difficult to control when they affect highly nonlinear characteristic in an IMM. Therefore, we propose an alternate approach to implement the controller using closed-loop control method to enhance the reliability. Through the development, fuzzy control algorithm is selected and it is programmed by an IL(Instruction List) and a LD(Ladder Diagram) on a PC based PLC. For the development of an IMM controller, PC based PLC of PCI card type, distributed I/O modules with CANopen, Industrial PC and HMI(Human Machine Interface) software are used.

A Mathematical Model for the Evaluation of Injection Molding Machine Control

This paper presents the development of a deterministic nonlinear lumped parameter mathematical model useful for the study and design of polymer injection molding machines and their associated controllers. The mathematical model was simulated on a digital computer and the results compared with experimental measurements taken in an existing injection molding machine. A comparison of these results showed that the developed mathematical model adequately predicts the transient behavior of averaged machine and mold variables. The resulting model is useful for control system design, machine parameter selection, and model redesign purposes.

A mathematical model for the evaluation of injection molding machine control

A mathematical model for the evaluation of injection molding machine control