Action locking gear of isolation switch

The locking gear includes knob, locking piece, and spring. The knob is sheathed on the locking piece. The locking piece also possesses a stopping arm. Being cooperated with the stopping arm, bosses on handle of isolating switch locks the switch at connection or disconnection state. One end of the spring is setup at the stopping arm; and the other end of the spring is setup at a fixed part of the isolating switch. The disclosed locking gear locks handle at connection or disconnection state so as to avoid error operation, and increase safety of isolating switch. Using rotational knob interlocks the locking piece so as to be able to release from locking expediently.