GRINDING METHOD FOR COMMUTATOR FOR DC MACHINE

PURPOSE:To obtain a well-ground surface avoiding dangerous works without lowering the efficiency of works, by a method wherein an auxiliary grinding appliance having a grinding box is provided for a locker ring for a DC machine and a grinding stone is pressed in the grinding box while the DC machine is rotated. CONSTITUTION:After a cover and a brush are removed, an auxiliary grinding appliance 15 integrated with a grinding box 9 confronting the surface of a commutator 11 is fixed to a locker ring 10 with a fastening bolt 3. While a DC machine is rotated, a grinding stone is inserted into the grinding box 9, and the grinding stone is pressed in and arranged to grind the surface of the commutator 11. As the result, operators are prevented from being caught in the machine and the grinding stone is prevented from flying dangerously, and the smooth ground surface can be obtained.