Abstract: Overedge crochet stitching provides a whip stitch appearance on both sides of a fabric. Each stitch has (a) two contiguous legs of thread on the upper surface of the fabric, extending from a needle hole to the edge of the fabric; and (b) two contiguous legs of thread on the lower surface of the fabric, extending from the needle hole to the edge of the fabric. Both legs on the upper surface are bent to form a two strand bight at the edge of the fabric. Both legs on the lower surface extend first through the two strand bight of the preceding stitch and then to a one strand bight which loops around the two strand bight of the current stitch. The method and apparatus involve a threaded needle which carries the thread through the fabric, a hook which pulls thread to the fabric edge above and below the fabric, and a retractable spreader which supports a leg of thread which extends up from the needle hole to the preceding stitch.

Abstract: A thread control mechanism for an overedge sewing machine uses only the movable driven components of the needle, lower looper, and upper looper, in combination with stationary thread guides, for feeding and controlling the threads used by the machine to form a seam. The lower and upper looper threads, i.e., the threads which pass through the eye of the lower and upper loopers, respectively, are each engaged by movable thread guides carried on the looper carriers for both loopers so that the coordinated movement of the two loopers cooperate to control and feed both looper threads. A needle thread takeup cam mounted on and driven by the needle arm drive shaft cooperates with stationary thread guides to feed and control the needle thread.