Design Of Yarn Tension On-line Monitoring System

Yarn tension is an important parameter as its size and stability directly influence the quality and efficiency of products during the textile process. The more the yarn tension vibrates,the worse the yarn quality is. The yarn tension will affect the appearance and comfort of the products made of the yarn. So the yarn tension is needed to be measured and controlled in the textile process to limit the vibration of the yarn tension.This paper puts forward a method by designing yarn tension on-line monitoring system against this background. The system mainly consists of sensor designing part and tension controling part and combines resistance strain sensor with MCU technology in order to transform tension to voltage,which is helpful for tension acquisition and the measurement accuracy improvement. At the same time this system can detect multi-channel sensor,display and save the real-time data,and user can adjust tension values by operating interface to make yarn tension stable.The hardware part is made up of bridge circuit,small signal amplifier circuit,multi-channel signal acquisition circuit,high precision AD conversion circuit and main control circuit. The software part is made up of the sensor output data modeling,nonlinear and temperature compensation,the communication between AD chip and MCU,storing data in database. The user part is mainly writing programme for Android tablet,providing the users with an interface that can be used to adjust motor state in order to achieve stable yarn tension.This system not only can solve time drift,temperature drift,noise interference issues of tension sensor,but can realize multi-channel signal acquisition,real-time display and preserve,that is on-line monitoring,so this system can be put into use.