Sewing machine

摘要

Process and appts. are to ascertain the thread contents of the spool. This is determined by measuring the frequency of revolution on the mainshaft and comparing it to that of the spool, and also in relation to the stitch length and depth of thread in the cloth, with all parameters registered in a micro-computer. With the information fed in, a programme is devised with a set formula, to constantly calculate, and indicate the amount of thread left on the spool as the machine runs, the information being available to the operator on an indicator.