Blocking device used for lifting shutter door of cage in vertical shaft

The utility model discloses a blocking device used for lifting a shutter door of a cage in a vertical shaft. The blocking device comprises cross rods slidably connected with a slide way on the cage; magnets are respectively arranged on two ends of a cross rod at the lowest end, and correspond to magnetic switches on a pot stabilizing support at a mouth of the well; and the magnetic switches are connected with a signal indicator lamp in an operation room via wires. The blocking device is proper in structure and novel in design; the magnets are arranged on the two ends of the cross rod, and when the shutter door is normally closed, the magnets are capable of corresponding to the magnetic switches which will send out signals to allow the signal indicator lamp to blink, so an operator is capable of performing pot descending operation; and on the contrary, the signal indicator lamp fails to shine, and the operator fails to performs the pot descending operation. According to the utility model, technical problems of