Abstract: In a double chainstitch sewing machine, a movable thread guide 37 is fixed to the lower end of a needle bar 1. A fixed thread guide 41 and a thread take-up cam 39 are fixed to a jaw 43a of a sewing machine arm 43. The thread take-up cam 39 has a cam section to be engaged with needle threads 51a, 51b from the fixed thread guide 41 to the movable thread guide 37, and takes up the needle threads oscillating up and down by vertical motion of the movable thread guide 37. Thread take-up members such as movable thread guide 37, fixed thread guide 41, and thread take-up cam 39 are disposed centrally at the lower end of the needle bar near the needle and in the jaw 43a of the sewing machine arm 43. As a result, there is no member for thread take-up moving at the upper side and front side of the sewing machine arm, and dangerous positions for the operator can be decreased.

Abstract: A chain stitch insert receivable in the bobbin case of a sewing machine is formed with a topside ledge which captures and consumes thread as a hook point carries a loop of thread around the bobbin case. The ledge enables the formation of chain stitches without the need for a special eyelet on the machine.