| Middle Density Fiberboard has been the main decorative product in the market. In our country, there are more than one hundred MDF product-lines, but most is in low automatic condition. The study of this paper is applied in the civil ones. In this paper, the automatic control system is designed based on the experience of on spot with programmable logic controller (PLC). The ladder program of the system is present in the paper. Some of the control program is modified to improve the efficient. Especial the programs in the mechanism which transform the board to presser. The use of the program in manufacturing indicates that it highly improved the speed of producing. In this paper, to improve the quality of fiberboard, fuzzy control theory is applied to the streamline in stress control of the center thermal presser. And designed the control software. The result shows the method applied here is right, controling the press in stable, which improves the quality of the fiberboard. Also in this paper, analyzing Production-Oriented program, control and communication of PLC, base on development technique of real-time operation system, Object-Oriented System Design, Direct Manipulation feature. We present the information control scheme of Multi-PLC Real-Time Control&Monitoring Platform, which emphasizes the reusability and expandability of software platform and human factor in application system instead of the monitoring in artificial. Based on the programming language visual C++6.O, used the ActiveX mscomm6.O, the system is developed according to the communicating protocol of PLC OMRON C200H Series produced by OMRON Corporation in Japan. Some strategies in the design of the software are discussed in detail: real-time communication scheme and strategy between multi-PLC and personal computer, coordination of multitask; group transmission of messages; relative separation and coordinate operation between user interface and application program; database design in the real-time system. According to the practice of automatic control program, the ladder program in PLC is stable. The real-time monitoring system is flexible. |
