PURPOSE: To beforehand prevent an accident resulting in injury or death by probably causal erroneous behavior of an operator at warehousing-delivering carriage operating time when the operator and a machine are opposed to each other in automated warehouse work. CONSTITUTION: On a part which cannot be sensed by the straight arrangement 10 of an abnormal button or a mat switch, photoelectric light sending-receiving units and reflecting plates at warehousing-delivering carrying carriage operating time, a light sending unit 4 is arranged in inside one place between a warehousing-delivering carrying carriage 2 and a member 3 to surround it, and reflecting plates 15 or the like are installed on a device reaching a light receiving unit 7 and columns 17 and 18 through reflecting plates 5 and 6, and when wheels of the warehousing-delivering carrying carriage 2 do not contact with a limit switch, they reach light sending- receiving units 13 and 14 through the reflecting plates 15 or the like in a diagonal line from the light sending receiving units 13 and 14. When the wheels contact with the limit switch, because of warehousing-delivering work time, the warehousing- delivering carrying carriage 2 exists in a stopping position, and the device is not actuated. Therefore, work is not hindered, and an entrance of the human body from all directions can be caught.