Research Of A Temperature Collecting And Controlling System For Wire Drawing Machines

The multi-point temperature control for plastic injection device is the important constituent part of wire drawing machines. Its functions of control, Multi-point temperature accuracy-tuned and the speed of response influence the product's quality which is output from wire drawing machines. This article designs a temperature collecting and controlling system based on the single-ship, and it is used to collecting and controlling the temperature in the plastic injection device of wire drawing machines.The multi-point temperature collecting and controlling system uses a hardware part which consists of 8051F and AVR the two kinds of single-ships, and it is combined by temperature sensor and power heating system. The long-distance operating system is carried out by computer through CAN bus. This system uses 24 bit high speed A/D converter which is integrated in the 8051F350 so as to realize its high precision in temperature measure. The temperature controlling part uses Silicon Controlled Rectifier to control every way which is over 20KW high-power, and we choose Atmega48 which has high-speed, low-power, and strong antidisturbance character as the MCU, changing the breakover of the Silicon Controlled Rectifier by sending out the control pulse to control the export power of the heating system and realize constant temperature controlling. Because of the heating system is a multivariable and nonlinear system with large time delay and heat inertia, in the process we use the PID Method (proportion, integral, differential) to calculate the temperature error (the difference between the given temperature value and the collected temperature value) and gain the control data. At the same time, the antidisturbance method what we have used in the software and hardware improves the fail-safe nature of the system.The software design of the system includes computer software and the single-ship software. Computer software takes Lab Windows/CVI6.0 as the developing platform to realize the dependable communication between single-ship and computer, and it copes with the data and displays it in time. It also has other functions, such as, memories data, displays curve, prints out and so on. The single-ship software chiefly realizes A/D conversion, PID control method, and the controlling pulse output functions and so on. In the program, we realize multi-point temperature control by combining the temperature collecting, PID computing process and computing result reasonably.The system has been delivered to the users on time, and has been used in a period of time. This system works well and steadily, so it can satisfy the demands both manufacturers and users.