PURPOSE: To avoid from a useless alarm and stopping, and to realize the continuous operation of a machine and the following high efficiency, by repeating the positioning operation and its confirming and detecting again when a poor positioning is generated from the member positioning confirming and detecting informations.
CONSTITUTION: The piston rod 50 of a cylinder 40 is connected to a door 60 for opening and closing the splash guard and the like of a machine tool, to a door device 110, and perseives the stroke ends of the drive cylinder 40 by the sensors LS1 and LS2 at the front and the rear stroke ends of the drive cylinder 40, and consequently, the opening and closing condition of the door 60 is to be confirmed and detected. As a result, the feedback of the opening and closing condition is carried out from the sensors LS1 and LS2 to a sequencer 10, and the sequencer 10 decides whether the positioning stop (the door closing) is normal or abnormal. When the positioning of the door closing is not perfect, an instruction to operate again is issued.
SUZUKI HIROYUKI
MITSUMA MARE
