The Research And Implement Of Rotational Temperature Transmitter For Heated Drawing Roller

Heated drawing roller, widely used in Chemical Fiber and Textile industry, is the key equipment of traction and stretch in FDY (Full Drawn Yarn). Stability and uniformity of temperature on the surface of roller affects directly the spinning quality. Stability is determined by detection terminal, control strategy, heater and many other kinds of factors. Uniformity is related to the way of heating, soaking, the materials of roller body, and other factors. The accuracy of temperature measurement of roller body directly affects the result of temperature control and furthermore determines temperature distribution uniformity. The roller body rotates at a high speed, so it’s more difficult to complete the design of the power supply and the signal transmission of temperature measurement circuit.This paper introduces a kind of rotational temperature transmitter used to measure temperature of surface of heated drawing roller. The device used contactless power transmission technology to supply power, which solved the problem on how to supply power when roller was rotating. And it used infrared communication technology to transfer the measurement data, which solved the problem on electromagnetic interference between wireless communication and contactless power. Through the transmitter analyzed measurement results from two PT100, the accuracy of the temperature was improved. The device could measure temperature, and it also completed speed measurement by the use of magnetic ring and hall element. Embedded high-performance microcomputer, it could not only accurately calculate temperature, but also intelligently analyzed operation state of roller body, so it was intelligent equipment with functions of data collection, analysis, alarm and communication. The software design of transmitter was with the sliding window filter for interference suppression and with the method of piecewise linear interpolation for improving measurement accuracy.The temperature transmitter designed in this paper is currently running with the heated drawing roller that is made by Zhengzhou Textile Automatic Control Equipment Ltd. The range of temperature measurement is-40to350degrees Celsius, and measurement accuracy can reach0.15degrees Celsius. There are alarm functions such as overheating, the damage to temperature sensor, etc. And the equipment runs continuously and stably over three months, measures accurately, operates reliably and has been put into production.