Anti-back-stranding device for coal residue single-bucket elevator

The utility model discloses an anti-back-stranding device for a coal residue single-bucket elevator. The device comprises a limiting switch, a supporting seat, a collision block and an electrical control device, wherein the limiting switch is fixedly connected to the supporting seat; the collision block is hinged to the supporting seat; the distance between one side of the collision block and a steel strand rope on the outer circumference of a winch is 5-8mm; the other end of the collision block is in contact fit with a roller of the limiting switch; the side, close to the winch, of the collision block is a cylinder in a horizontal state; the length of the cylinder is smaller than the diameter of the winch by 20-40 mm. An anti-derailment limiting contact switch is arranged at the 5 mm position of a steel wire winch; under the normal condition, a steel wire rope is free of derailment, groove disengagement and steel stranding on the winch, the distance between a steel wire and the limiting contact switch equals to 5 mm, and the limiting contact switch is always in a turn-on state; when coal is slightly gathered at the bottom of a pit track, the steel rope slightly jumps over a groove and is not stranded; when the thickness of the steel rope is 30 mm and the distance between the steel rope and the limiting contact switch is shortened to be smaller than 3 mm, the limiting contact switch is immediately turned off.