A Breakage-Stop System for Linen Wet Spinning Frame

A multi-way control system for spun yarn breakage detecting and tow stopping is presented for linen wet spinning frame upgrade in medium-sized businesses of southeastern China. The signals from periodic rotations of spun yarns are picked by piezoelectric sensors. After input protection and multiplexers, the weak voltage signal from gated channel is processed through links including voltage following, passive high-pass filter, active low-pass filter, in-phase and reversedphase proportional amplifying, precision full-wave rectification, retardation voltage comparison, etc.. After regulated at a zener diode link, the final electrical level is sent to LPC2132 processor which gives trigger signals to actuators when yarn breakage is detected. In the corresponding actuator channel, armature of electromagnet will be pushed off to stop tow feed and the red LED will be lightened to warn spinner. Circuit board units for signal amplifying, conditioning and actuator driving were designed for controlling 24 yarn channels simultaneously. The simulation result and field test verified the circuit accuracy and programmed effectiveness.