Monitoring And Control System Of Injection Molding Machine Based On CAN-BUS

It is the most important development in autocontrol of injection molding machine that microprocessor was applied in injection molding machine, the system of microprocessor controlling injection molding machine can realize many function such as keyboard input,screen display,system function,system checking,signal feedback and emendation. Operator can input instruction or data base on the problems displayed on the screen, For instance, the temperature of stuff canister,the distance of mold opening and clamping,injecting pressure,injecting speed,pressure of keeping press,gore out time cooling time,production periods etc. After the data or the instruction was inputted, the system then will run according to the inputting data or instruction, at the same time the system of microprocessor starts to watch and check whether the actual data and the expected data are identical, if find difference it will immediately feedback to the processing system for correction in time. This can not only ensure the reproduction and repeating precision, but also can realize fast debugging. Most modern controlling systems of injection molding machine are qualified with communication interface and bus function, which convenient for controlling online with host computer. What this text tell is applying CAN-BUS in distributed controlling system to monitor and control the working course of injection molding machine. Distributed system has many merits: as economy, various controlling cells are connected by CAN-BUS take on higher capability and price ratio than controlling the whole system by one controlling cell. As velocity, distributed system is very suitable for the controlling system which has dispersive task,frequent communication and need a great deal of processing capability, because each controlling cell only process the local things, so it ensure fast response when performing the alternating tasks. As extending system, distributed system can make proper extension when the systemic workload are increased. As reliability, it will not result in the malfunction of whole system when some exceptional cell in system has problems, other controlling cells can work on yet. CAN is a kind of efficient serial communication network which can support distributed control or real time control. It includes three module as driving system,comfort system and information system . CAN is a kind of real time data bus virtually, the address of the signal reciever is needn't to be given, the signal sender send the datas which have been coded safely to all signal recievers; High-speed CAN-BUS can transmit 32 bytes data per millisecond; Each signal receiver read the data they want actively from the bus; Adopt non-destroyed bus arbitration technique, It won't encounter network paralysis when the load of network is very heavy; The farthest distance of direct communication of CAN can reach 10Km( the speed under 5bps ), the highest communication speed can reach 1Mbps ( here the longest communication distance is 40m ). The most merit of CAN-BUS technique is it reduce the number of wiring harness and the pins of the controller interface, at the same time it can easily and quickly realize the functions as program online,diagnose online and even multiple controllers work together etc. Labwindows/CVI is a kind of software develop platform for virtual instrument facing the computer testing and controlling field, it organically combined the function powerful,flexibly used language C with the special testing and controlling tools for data collection,analysis and display. Its integrated develop environment,alternative programmed method,function panel and abundant lib functions...