Temporal Metric
Precise duration of the weft yarn journey from the main nozzle to the arrival sensor determines the timing of the loom’s mechanical cycle. Recording flight time milliseconds allows the control system to adjust the relay nozzles for optimal air usage. If the duration is too long, the yarn might be caught by the closing shed, resulting in a fabric defect.
The temporal measurement is sensitive to changes in yarn hairiness and humidity levels in the mill.
Synchronization Requirement
Loom controllers use the flight time milliseconds data to synchronize the cutting of the yarn and the beating of the reed. Flax yarn has a rougher surface than cotton, which increases air drag and changes the travel time. Adjusting the nozzle pressure based on real-time feedback keeps the flight duration within the target range.
A narrow window of flight time ensures the loom can operate at high speeds without stopping for weft errors. Automatic adjustments occur during the weaving process.
Shed Adjustment
Correct flight time milliseconds values prevent the yarn from arriving too early or too late relative to the reed movement. Arriving early causes the yarn to bounce back and creates a loop. Late arrival leads to an incomplete pick.
Maintaining this window is necessary for continuous loom operation.
