To reliably reconnect respective carrying carriages to each other when plurally connected carriages individually ascend or descend by providing engaging means which are rotatably supported by end parts of the carrying carriages and can engage with or separate from the adjacent carriages at ascending or descending time.

This connecting device is arranged in respective end parts of a horizontal frame 11 of carrying carriages. A connecting protrusion 31a to engage with connecting holes 11a arranged in the end parts of the horizontal frame 11 is protrusively arranged on both ends of an under surface of a connecting member 31. This connecting device is composed of a tension spring 32 to energize a posture of the connecting member 31 in a prescribed posture necessary for carriage connection, that is, so as to turn in the lengthwise and horizontal direction of the horizontal frame 11 in a condition where the connecting member 31 and the connecting protrusion 31a are engaged with the connecting holes 11a. The connecting member 31 can rotate to the connecting holes 11a, and can pass without hindrance even if the respective carrying carriages come to a curved ceiling carrying passage in a connected condition. The carrying carriages can engage with or separate from the connecting holes 11a of the adjacent carrying carriages at ascending or descending time.