SEARCHING METHOD FOR CENTER POSITION OF CIRCLE

摘要

PURPOSE:To permit positioning of a center of a circle and centers of plural detectors accurately and quickly by moving the detecting device in the direction and by the amount settled beforehand, in accordance with the detector by which the inside position of the circle to be detected is being detected. CONSTITUTION:A detecting device 2 is constituted in the manner of providing the plural, e.g. four detectors on a circumference at nearly constant intervals. The detecting device 2 is allowed to move in a vortical state until the time when the inside position of a hole part 51 on a roll status article 5 to be detected is detected by anyone of these four detectors. Until the inside position of the hole part 51 is detected by all detectors after the inside position of the part 51 is detected by anyone of the detectors, the action is repeated to move the detecting device 2 in the direction and by the amount being settled beforehand in accordance with the detector by which the inside position of the hole 51 is detected, then the alignment of the positions is made for the center of the detecting device 2 and the center of the hole part 51.