Earthing switch operation interlock

The utility model provides an earthing switch operation interlock, includes control rod, lock tube and U type support, outer wall on the lock tube is equipped with the lug, cavity in the lock tube is interior polygon, the cross -section of the end of control rod be with the lock tube cavity in the outer polygon cross -section of polygonal outward appearance adaptation, be equipped with the perforation on the curb plate about U type support, the medial surface of one of them curb plate of U type support is equipped with horizontal recess, the control rod passes a curb plate of U type support and bores a hole, is equipped with the step face on the control rod, and the operation rod cover has the spring, and push up respectively on the terminal surface of lock tube and the step face on the control rod at the spring both ends, and the lock tube passes the perforation that is equipped with the notch board, and at initial condition, the spring pushes up the lug of lock tube outer wall in the recess of one side of U type support inboard side, and the recess of U type support limits the rotation of lock tube. The utility model discloses increase and interlock with the reverse of back door, must close the back door earlier and can operate earthing switch, simple structure, mistake performance greatly increased is prevented to the good reliability.