Analysis of thread tension in sewing stitch formation

Sewing is a process of joining fabrics, its quality being determined by a number of factors. As textile fabrics used in garment and technical textiles manufacturing processes differ considerably, selection of optimal sewing machine parameters is not an easy task, since they should be matched with both the properties of the thread used and the properties of the workpiece processed. The investigation described is aimed at studying the impact of stitching speed as a sewing machine parameter and thread fineness on the strains the thread is exposed to in stitch formation. Analysis of the strain measured, i.e. tensile force of the thread in sewing constitutes a basis for determining the tension of the thread in stitch formation. Analysis of the results for tensile force as dependent upon the angle of main shaft turning indicates that thread fineness and stitching speed have a considerable impact on strains in the thread. Stitching speed influences the force in question, as well as the width of the peaks in thread tension, which is directly related to the strains the thread is exposed to.