Sewing machine

Abstract

The invention provides a sewing machine, which can obtain the seam of desirable double multi-thread chain stitch where looper string gets caught by the loop of needle thread on the reverse side of cloth while the looper string is loosened without leaving any traces on the cloth, and also can stably obtain the sewing-goods with good quality. The sewing machine is composed of a retainer rod 30 is provided which projects and withdraws backward and forward within a plane roughly in parallel with the feed surface of the cloth W while interlocked with the rise and fall of the needle 1, and this retainer rod 30 catches the looper thread 20 at the projection side of the looper 2 ahead of the needle 1 when projecting rearward, and holds the caught looper thread 20 between the rod and needle 1 under tension.

Description

technical field [0001] The present invention relates to a sewing machine, in particular to a sewing machine that uses a needle that penetrates the cloth on the needle board to move up and down and a bottom needle that moves forward and backward in the left and right directions under the needle board to perform sewing. And sewing machines for safe sewing. Background technique [0002] The sewing action of a double-thread lockstitch sewing machine with one or more needles that hold the needle thread and move up and down through the fabric on the needle board and the bottom needle that holds the bottom thread and moves forward and backward under the needle board in the left and right directions is repeated in the following order Operational: the loop of needle thread spun out by the downward movement of the needle and left under the needle plate when it enters the transition to the upward movement is caught by the bottom needle which enters synchronously with the upward movemen...

AI Technical Summary

Problems solved by technology

[0012] However, since the above-mentioned positioning needle is in order to catch the bottom thread 20, it is a structure that penetrates the cloth w at the same time as the needle and reaches under the needle plate, so when sewing is performed with a sewing machine having the above-mentioned positioning needle, as shown in FIG. 3 , Holes H, H... are formed side by side on one side of the stitching of the double loop (the entry side of the bottom needle) along with the penetration of the positioning needle. The existence of holes H, H... becomes a problem

[0013] In addition, in recent years, sewn items (shirts, handkerchiefs, etc.) using fabrics that do not require ironing after washing and have a shape memory function have been put into practical use. When sewing parts, there will be concerns that good processing quality will not be obtained due to the excess of the above-mentioned empty holes H, H...the original traces when they were formed.

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