METHOD FOR FORMING A TWO-THREAD TWO-LINE CHAIN STITCH AND A DEVICE FOR ITS IMPLEMENTATION Russian patent published in 2021 - IPC D05B93/00 

FIELD: clothing industry.

SUBSTANCE: invention relates to the clothing industry, in particular to two-thread two-line chain stitches and methods for their formation, and can be used in sewing knitwear. It is aimed at expanding the arsenal of easy-to-use tools aimed at obtaining a two-line double-line chain stitch of high quality and high reliability of the resulting seam. The device for forming a two-thread two-line chain stitch consists of a needle mechanism that contains left 1 and right 3 needles mounted on a line perpendicular to the line of movement of the material 5, and a looper mechanism, the left 6 and right 7 loopers are located parallel to each other and horizontally across the stitch with the possibility of rotation around its axis by 90°, while the left looper is located behind the left needle, and the right looper is located in front of the right needle, at the end of each of the loopers there is a widener 8 and 9 in the form of a fork 10 and 11 for the passage of the needle, and on the horns of the fork there are spouts 12 and 13 for removing the loop-inlet from the needle and a groove 14 and 15 for directing the thread when loops 16 and 17 are formed. The method for forming a two-thread two-line chain stitch consists in repeatedly piercing the material. After each piercing of the material, when two parallel needles are lifted, loops are formed over their eyes, which include the spouts of two converging horizontal loopers, while the threads are placed in the grooves of the forks of the wideners, after the needles exit the material, the loopers continue to move towards each other, forming loops between the puncture of the needles in the material and the forks. When the wideners take the position opposite the needles, the loopers rotate around their axis at an angle of 90° counterclockwise around the direction of their movement, substituting forks with the threads of the loops opposite the opposite ones, then the material moves by the amount of the stitch to the place of the new puncture and forms intersecting loops from below the material, then the needles, moving down, piercing the material, form the upper threads of the stitch and tighten it. Then, they enter the forks with loops, then the loopers begin to diverge, turning around their axis at an angle of 90° clockwise, leaving the loops put on the needles with threads.

EFFECT: after forming a two-thread two-line chain stitch, the process of forming stitches is repeated and a two-thread two-line chain stitch is formed.

2 cl, 9 dwg