Yarn Length Measuring System

The above diagram shows the schematic configuration to the length measuring counter..

The counter accepts rotation pulses from the proximity and yarn present status from the yarn detectors and measures length of the yarn wound on the cone.When preset length is reached the counter activates the yarn cutter and also disconnects power to the drum motor. The set length Is reloaded for the next cone.

The motor can be restarted by the START/STOP key(K2) on the counter.

Process paramenters such as set length, pulse ratio etc can be set by the three keys on the remaining length Is displayed on the screen. Key K3 to toggle between remaining length and the counter also activates the yarn cutter in case of missing ply to prevent winding of undesired single yarn. The counter also stops the motor and the length count

A yarn break detector having a collecting electrode type sensor to which a continuously moving yarn is lightly contacted. A gate electrode of a field effect transistor is connected to the sensor and a relay circuit is connected in series to a drain electrode of the transistor. Normally, the field effect transistor of high input impedance is operated to its one condition by the collected electric charges from the continuously moving yarn. When the yarn break or cutting off occurs, the collected charges on the sensor disappear and then the field effect transistor is changed into its other condition, thereby the relay circuit produces an alarm signal.