Return system and return method

摘要

The conveying system of this invention is equipped with the conveyance controller which outputs the track | orbit, the some ceiling conveyance vehicle, and the conveyance command of the FOUP with respect to a ceiling conveyance vehicle. The transfer controller has a predetermined waiting time after the first FOUP becomes the recovery wait state when the first FOUP placed on the downstream port is in a recovery wait state and the FOUP is not mounted on an upstream port. Until this elapses, it waits for the output of the conveying instruction which instruct | recovers the number of 1st FOUPs until the ceiling conveyance vehicle which conveys a 2nd FOUP to an upstream port is grasped | ascertained, and the 1st FOUP becomes the state of waiting for a recovery. If the waiting time has elapsed from the above, a return instruction instructing the number of times of the first FOUP is output.