SEWING MACHINE

PROBLEM TO BE SOLVED: To use electric power generated by a generator using rotation of a rotation shaft and reciprocation of a driving shaft with sewing operation as a power source for an electronic device. SOLUTION: A sewing machine main shaft disposed at an arm portion of a sewing machine is externally fitted with the generator composed of a PM type stepping motor, the sewing machine main shaft is rotatably driven by a sewing machine motor with the start of sewing, and the electric power is generated by the generator. The electric power generated by the generator is rectified by diodes D1-D4 and smoothing capacitor groups 31A and 31B to be inverted to direct current, converted into a constant voltage with a zener diode 27, and supplied to an input terminal (VCC) I4 of a maintenance CPU 26 through a first constant voltage line L3 or second constant voltage line L4 and a common 5V line L5 for operating the CPU 26. A comparator 38 outputs a signal at "H" level, when the direct voltage supplied to one input terminal through a voltage supply line L1 is higher than the reference voltage (approximately 0.5 V). COPYRIGHT: (C)2006,JPO&NCIPI