The winch converts the electric energy into mechanical energy through the motor, that is, the rotor of the motor rotates the output, through the triangle belt, shaft, gear, and then drives the drum to rotate after deceleration. The reel winds the wire rope 7 and passes through the pulley block to make the crane hook lift or drop the load Q, change the mechanical energy into mechanical work, and complete the vertical transport loading and unloading work of the load.