PURPOSE: To dispense with a connection on the conveyed article supporting means side of belts of wires housed in different belts by reliably detecting cutting of the belts.

CONSTITUTION: Wires 24a, 14b are respectively housed in four belts 4a to 4d for suspending a raising and lowering stand 5 across the total length. The wires 14a, 14b are connected to each other on the raising and lowering stand 5 side of respective belts 4a to 4d, and terminals 15a, 15b are projectingly provided on the opposite side. The wires 14a, 14b of respective belts 4a to 4d are connected to each other in series by connecting lines 16. The terminal 15a of the wire 14a of the belt 4a is connected to an output part 19 for outputting the specific voltage. The terminal 15b of the wire 14b of the belt 4d is connected to a judging circuit 21 through an input part 20. The specific voltage is always output from the output part 19.