Abstract: A mechanism for seizing and holding a thread, particularly the looper thread, of a chainstitch sewing machine to insure needle penetration of the thread triangle thereby assuring enchaining of the needle thread with the looper thread. Such mechanism includes an oscillatable thread spreader which transversely moves across the looper's endwise path of travel. The spreader motion being in timed relation with the stitch forming instrumentalities such that its effectively travel extends between the looper eye and the reciprocal path of the needle arranged closest to the looper eye when the looper is at its extreme loop seizing position.

Abstract: A needle thread control mechanism for sewing machines which permits a machine operator to adjust the stitch tightness includes a thread take-up mechanism arranged wholly outside of the machine frame and a thread controlling mechanism arranged directly between the needle thread take-up mechanism and a thread supply source. A thread controller, adapted to cooperate with the thread take-up mechanism, is also provided.