Research of variable parameters of needle thread take-up mechanisms and development of recommendations for adjusting multi-thread chain stitch sewing machines

Abstract

The purpose of this research is to develop specific recommendations for optimizing the adjustment of the thread take-up mechanisms of typical chain stitch sewing machines based on the analysis of the thread take-up process. These recommendations are intended to help manufacturers and machine operators achieve maximum productivity and increased product quality, while taking into account the specific technological parameters of the operations performed on these machines. The research is aimed at increasing the efficiency of the sewing process, reducing machine setup time, and improving the overall result of the technological process in the sewing industry. The research uses an analytical method of determining and investigating functions of the actual thread take-up as the instantaneous sum of sections of the take-up contour when adjustable parameters of the mechanisms are changed, taking into account accepted assumptions. In the research, an analytical method was used to determine functions of the actual thread take-up as the instantaneous sum of sections of the take-up contour, taking into account the change in regulated parameters of the mechanisms. At the same time, assumptions were made that has simplified analysis and modelling of this process with sufficient accuracy of calculation results. The scientific novelty of this research lies in discovery of new relationships and establishment of regularities that determine influence of adjustable parameters on the nature and scope of the thread take-up function in chain stitch machines. Further re-search in this area can be aimed to the development of more efficient methods of adjustment and optimization of needle thread take-up mechanisms, as well as to the implementation of new technologies in pro-duction to improve productivity and quality of sewing operations. The obtained results became basis for the development of nomograms for determining the optimal values of adjustable parameters for needle thread take-up mechanisms of typical flat chain stitch machines, taking into account technological parameters of specific operations. These nomograms allow operators and manufacturers of sewing machines significantly simplify adjustment of these mechanisms when using operational equipment or when switching to other technological operations. The obtained results can be applied directly in production during adjustment or repairing of specified ma-chines to increase their productivity by reducing adjustment time and for improving the quality of the technological process.