Design and Implementation of Yarn Tension Measurement System during Weft Insertion on Air-Jet Loom

Yarn tension during weft insertion is one of important factors which affect fabric properties. In air jet loom, many components have an influence on yarn tension, such as clamp, main nozzle, sub nozzle, brake, and the drum. In this paper, a measurement system for yarn tension experiment which based on a 32-bit Cortex-M3 embedded processor was designed and implemented. The system can control components at fixed time interval which is set by a supervisory computer, acquire yarn tension converted by a contacted electromagnetic induction tension sensor, and then transmit tension data to software system by Ethernet module. An experiment is conducted for research character of yarn tension driven by air flow. The experiment results indicate that the nozzle pressure and yarn diameter play an important role in yarn tension during weft insertion on air-jet loom. Besides, the delay of magnetic value is also considered under different nozzle pressure.