As a kind of plastic processing and moulding machines, the products of plastic injection moulding machine have a wide range of applications in various fields. Injection molding is a complex technology, and the product quality is closely related to various performance parameters, so it is necessary to accurately acquire and adjust all the performance parameters. Many testing parameters, multi-signal interference, and the process parameters of pressure and temperature rapidly changing, which requires high testing technology . The main disadvantages of traditional testing are low data accuracy, low testing speed and complex testing operations. Virtual instruments (VI) , a newly developed testing instrument was appeared as the result of the combination of computer technology and testing instruments technology. As an innovative product of traditional testing, VI is a computer-based data acquisition system. It is based on PC platform, Which make it convenient to use the software and hardware resources of PC and get the ability of data processing flexible. With VI, a testing system can be easily built for different requirements.The author of the paper designed a data acquisition system based on computer. The system included design of hardware system and software system. Finally, this paper introduced several examples of scientific research and teaching, through which we can find the characteristics and application of this system.In the part of expounding the design of hardware system, this paper concluded parameter testing methods of injection moulding machine and their signal features. Then introduced the hardware architecture and the main characteristics of this testing system, the selection of data acquisition devices and the computer. Finally some common signal testing systems used in this system were explained.In the next part of expounding the design of software system, this paper first introduced the method of multi-channel data acquisition system using LabVIEW graphical programming language, and then analyzed the module design of parameter configuration, data acquisition and processing, and data playback in detail, which fully embodied that the system had the characteristics of conveniently developing, flexible operation and high programming efficiency. It is also showed that the system of computer-based platform had a function with multi-instrument'data analysis and processing. |