Modern electric sewing machines are having more electric and electronic applications than mechanical applications. But, due to the long-term operation and improper usage certain electronic issues can occur in these machines. Besides, there may be mechanical errors as well. Most of the garment factories are having their own repair centre to repair their machines. After repairing a machine, those machines should be tested for 45 minutes to ensure the sewing machine is production
floor worthy. In some of the sewing machines there is an in-built auto run parameter which sets the machine to autorun mode and the machine is tested in this mode after repairing. There are many brands of electric sewing machines in which this parameter is unavailable. As a solution for this problem a prototype is designed and implemented to test machines after doing a repair as per the manufacturer’s recommendation. The test kit designed is named as AOC unit which stands for Automatic Option Control unit. This option controlling unit is designed to install to any sewing machine externally and the servo motor used in the unit is attached to the speed controller of the sewing machine. Sewing machine speed controller has been designed by the manufacturer to provide command signals to the microprocessor when the pedal position is changed by the operator. AOC unit actuates the speed controller without any interference of the operator and sewing machine operates
automatically within a given time. This operation is stopped by the countdown timer in the unit at the end of the set time.