RU2068898C1 - Method for forming stitching bifilar line from similar shape stitches of different filaments - Google Patents

Abstract

FIELD: sewing industry. SUBSTANCE: method involves drawing stitch loops of different filaments from different sides of material in direction opposed to that of material surface for length exceeding half the length of stitch; inserting other filament into stitch loop and tightening it. EFFECT: increased longitudinal strength (elasticity) of stitching seam and increased length of stitch. 2 dwg

Description

 The invention relates to mechanical engineering for the clothing industry and can be applied in the development of sewing machines and garments.

 Known two-thread chain sewing stitch, consisting of simple stitches with a loop on one side of the material and stitches in the form of a chain of three threads on the other side of the material.

 Also known is a double-thread shuttle stitch, consisting of stitches with the same and located on different sides of the material stitches with loops interwoven between the sewing materials.

 The prototype of the invention (device) is a double-thread shuttle stitch.

 A known method of forming a double-thread chain stitch, comprising forming a loop of a stitch of the upper thread on the opposite side of the material, threading it with the lower thread to form a chain of three threads, tightening the loop and moving the stitch to the length of the stitch.

 There is also known a method of forming a double-thread shuttle stitch from the same stitches of different threads located on different sides of the material, comprising forming a loop of a stitch of the upper thread, threading it with the bobbin thread, tightening the loop and moving the stitch to the length of the stitch.

The prototype of the invention (method) is a line formation method according to [1]
The disadvantages of the prototypes of the device and method are the low elasticity of the stitch and, therefore, the low longitudinal strength of the seam, as well as the fact that the length of the stitch of the stitch is small and equal to the distance between adjacent punctures of the material with a needle.

 The low strength of the seam is a consequence of the “rigid” design of the stitch of the stitch, when the thread takes a little more than the length of the stitch to form it (low possibility of stretching the stitch along the stitch). The equality of the stitch length to the distance between adjacent punctures of one needle determines that, to ensure the necessary strength of the seam across the stitch, the needle must puncture the material with a high frequency (with a short stitch length), which naturally limits the performance of the sewing machine.

 The aim of the invention is to increase the strength (elasticity) of the seam and increase the length of the stitch.

 This goal is achieved by the fact that in a two-thread stitching stitch, consisting of stitches that are identical in shape and located on different sides of the stitched material, with a loop attached, the loop of each stitch is located on the opposite side of the material, facing the opposite side to the material movement and fixed with another thread, and the stitches different threads alternately partially overlap each other.

 This goal is also achieved by using the method of forming a sewing double-thread stitch from identical stitches of different threads located on different sides of the material containing the loop, threading it with another thread, tightening the loop and moving the material along the stitch, in which the loop of the stitch of different threads is pulled from different sides material in the opposite direction of movement of the stitch by an amount exceeding half the length of the stitch, and in this position they are pierced with another thread.

 This design of the stitch and the method of its formation provide stitches of "low stiffness", since the presence of a loop of each stitch more than half the length of the stitch increases 2.5 times the length of the thread spent on each stitch, and consequently increases the elasticity to the same extent stitch along the stitch. The fact that the stitches of different threads alternately partially overlap each other means that along the length of the stitch of each thread there is another material fastening by the loop of the stitch of the opposite thread, which doubles the lateral strength of the stitch. Therefore, to ensure the required stitch strength in this direction, the stitch length of each thread can be doubled (the same total number of material punctures per unit length of the seam), which means that at the same frequency of movement of each needle, the performance of the sewing machine can also be increased almost doubled.

 Comparison of the claimed technical solutions with the prototype made it possible to establish compliance with their criterion of "novelty." In the study of other known technical solutions in the art, the features that distinguish this solution from the prototype were not identified, therefore, the proposed invention ensures its compliance with the criterion of "significant differences".

 In FIG. 1 depicts a sewing two-thread stitch, where 1 and 2 are the upper and lower stitches, respectively; 3 and 4 loops of the corresponding stitches; 5 and 6 places of fastening the stitch loop with the thread of another stitch (with another thread); in FIG. 2 the appearance of the stitch on the surface of the material, a top view, where l is the length of the upper stitch.

 The proposed line and the method of its formation can be carried out manually or on a sewing machine having the needle bar, looper, and material feeding mechanisms that are usual for this class of machines and working according to the proposed method (for example, on a domestic 1622 C sewing machine with an increased stroke of the loopers together with the loop) .

 The technical and economic efficiency of the proposals is based on improving the quality of garments, especially from elastic fabrics (increasing the strength and elasticity of the seam) and significantly increasing the productivity of sewing operations (by lengthening the stitch while maintaining the quality of the seam and the speed of the camshaft of the machine). YYY1

Claims (1)

 The method of forming a two-thread sewing stitch from the same shape of stitches of different threads, which consists in the formation of loops of threads on both sides of the material, piercing them with loops of opposite threads, laying the loops on the material, characterized in that before laying, each loop is stretched to a predetermined amount, and its penetration with a loop of another thread is produced after laying.

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