PURPOSE: To save the area and smoothly perform delivery by providing a clamp mechanism opening/closing control means controlling opening/closing of a clamp mechanism provided on either an elevatable part provided on the inlet part and the outlet part of a carrying lane and an empty pallet storage lane or a robot moving a work to a prescribed position.

CONSTITUTION: A robot hand is operated, so as to lead a work W to the inlet part of a storage part. At the inlet part of the storage part, the work W grasped with the robot hand is positioned between clamp arms 31 in open state, and by operating an air cylinder 71 to advance, the work W is held with the lower clamp arms 31a. By releasing grasping of the robot hand, the work W is delivered to the pallet P side, and the work W becomes in the state of being suspended with the pallet P. When one work W is suspended with the pallet P, a carrying lane is operated by a prescribed pitch, and the suspended work W is carried toward an outlet together with the pallet P.