Chain stitch sewing machine has thread tensioner which sets up yarn tension, so that thread loop is bent based on last needle location

摘要

The rotary looper forms the thread loop by pulling the thread. A thread tensioner sets up yarn tension, so that thread loop bends if formed before last needle location and thread loop does not bend if formed in last needle location. The thread tensioner supplies the thread to needle by thread feed zone. The pressure regulating device changes the pressure of thread tensioner, so that thread loop may or may not bend depending on last needle location.