METHOD FOR PREVENTING STITCH FROM COMING APART, DEVICE FOR PREVENTING STITCH FROM COMING APART, AND STITCH STRUCTURE

摘要

A thread hook (3) and a looper thread holding body (6) are disposed on the rear side of a needle entry position on a sewing machine. The thread hook (3) and the looper thread holding body (6) swing and come close to a looper once a normal sewing process completes. A hook part (3b) at the tip of the thread hook (3) holds a needle thread loop captured by means of the looper, and a thread receiving part (6a) disposed on the tip of the looper thread holding body (6) holds the looper thread extending from the looper to a sewing fabric, the hooked part (3b) and the thread receiving part (6a) each being located on the front side relative to the needle lowering position. The sewing machine performs a sewing process amounting to at least one stitch by maintaining the position of the needle thread loop and the looper thread. As a consequence it is possible to effectively prevent stitches from coming apart which typically occurs in a multi-thread chain stitch without being influenced by the tensile force of the needle thread and the looper thread.