A model on stitch tightening process of lockstitch machine

Abstract

A model of stitch tightening process in lockstitch machine is formulated to predict the needle thread peak tension during stitch tightening and the position of needle and bobbin thread crossover point i.e. y-value. This y-value is then used to predict the thread consumption in a lockstitch seam. A computer program in C language is developed based on the model formulated in lockstitch machinery to predict needle thread stitch tightening tension and the position of needle and bobbin thread crossover point i.e. y-value. The developed model is validated qualitatively by studying the effect of different variables on peak value of needle thread tension. The model is also validated quantitatively by comparing the experimental and predicted values of peak tension and stitch length. A satisfactory predictive power of the model is observed which validates the developed model.