Sewing needles needle systems

One of the more recent types of compound feeding system is the X-feed system by Xi an Typical Industry Co., Ltd. (Xi an, China). In this system, the drop-feed is combined with the needle-feed, but unlike a normal feed-dog, the feed-dog in this system is split into two parts, with each being active in about half of the sewing cycle. The fabric is thus supported between the presser-foot and feed-dog in a more even way throughout the stitch cycle. Jana and Khana (2014) studied this new feeding system and in their experiments found that this system reduced ply slippage and produced flatter seams than the traditional drop-feed. More details of X-feed is described in Chapter 11. 

In a triple-feed machine, the drop-feed combines with the needle-feed and with a presser-foot, which also moves synchronised with the other two feeding elements. This system is able to virtually eliminate the problem of feed pucker, but its mechanical complexity results in a high price and a limitation in the machine s sewing speed. It is almost exclusively reserved for applications in heavy materials, such as leather goods. 

Rocha (1996) used a piezoelectric sensor inserted into the needle bar of an industrial overedge sewing machine, a measurement system that was further developed by Carvalho (2010). With this equipment, it is possible to measure needle penetration and withdrawal force at industrial speeds. Rocha found that, among other material properties, bending rigidity and drape factor were related to needle penetration forces. It was possible to demonstrate the relationship among needle size, sewing... 

Proper adjustment of the stitch length, sewing threads and needles, according to the type of fabric (structural jamming appears mainly in dense, lightweight fabrics) Correct adjustment of thread tensions Proper selection of the feeding system (on knits and stretch wovens, use differential feed and minimum of pressure-foot pressure)... 

Two sewing thread system (needle and gripper thread)... 

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