Design and implementation of online measurement and control system for mold cavity temperature

In order to achieve high process efficiency and ideal quality for thermoplastic products, the accuracy of temperature measurement and the response speed of temperature control are critical. A set of on-line measurement and control system for mold cavity temperature was designed and implemented. The system consists of two parts: the temperature measurement and control instrument and the PC monitoring software. The instrument uses each cavity as the monitoring point, and uses the thermocouple to measure the temperature. Through the ADC conversion, the cavity temperature can be obtained, and the temperature can be adjusted in a suitable range by controlling the heating and cooling valves of each cavity. The instrument transmits the measured temperature data and the valve status of each channel to the monitoring software via WiFi. The software draws the temperature curve, stores and judges the temperature data, and issues an alarm if it is not within the threshold range. The system can simultaneously monitor 12 cavities. The measurement temperature is between 0-250 °C, the maximum acquisition speed of the system single channel is 0.02 seconds.