Abstract: A control device that determines tape reference positions having a fixed positional relationship with first origin positions based on first positions of tape feeding devices when leading ends of carrier tapes are detected and the first origin positions of the tape feeding devices immediately before leading end detection. Then, after determination of the tape reference positions, an interval between cavities is calculated based on a detection cycle of transmitted light amounts detected by light being transmitted through empty cavities. In addition, when a phenomenon, in which a detected light amount is equal to or smaller than a threshold, consecutively occurs after calculation of the interval between the cavities, it is detected that components are accommodated in the cavities.