1986 Volume 27 Issue 8 Pages 347-351
The stretchability of seams sewn by a chain stitch sewing machine (stitch type: 101) has been studied. The results obtained were as follows.
1) A linear relationship was observed between stretchability (stretch ratio at break) and thread consumption of seams.
2) The thread tensions were obtained during machine sewing. The tension Fr·p observed when the thread was held by the center of a looper body was connected with the tightening of stitches and was important for the thread consumption of seams.
3) A linear relationship was approximately shown in a log-log graph between (lt-la) and Fr·p. Where, lt; thread length per stitch in the ideal state which is equal to (3le+2t), la: thread length per stitch obtained from seams, le: stitch length, and t: thickness of fabrics sewn.
4) By using the results mentioned above, it is possible to predict the thread consumption and the stretchability of seams by using Fr·pmeasured in sewing process.
