| 摘要 |
PURPOSE:To enable the easy determination of a flaw position with respect to the direction at a right angle to the conveyance direction of a material to be examined, by detecting the time difference between the respective output signals of the 1st detector having a slender flaw detection region in the direction at approximately a right angle to the conveyance direction of the material to be examined and the 2nd detector having a slender flaw detection in the direction forming a specified angle to said conveyance direction. CONSTITUTION:The detection of a flaw position with respect to the direction at a right angle to a conveyance direction is made possible as well by the difference in appearance time between the flaw detection signal of the 1st flaw detector 1a and the flaw detection signal of the 2nd flaw detector 1b. More specifically, the flaw position (y) in the direction at a right angle to the conveyance direction is given by the equation where the conveyance speed of a material 8 to be examined is designated as Vm/s, the angle of intersection between the longitudinal direction of the 1st flaw detection region 2 and the conveyance direction as pi+alpha rad, the angle of intersection between the longitudinal directions of the flaw detection regions 2a, 2b as beta rad and the difference in the appearance time of the above-mentioned flaw detection signals as (t) sec. Therefore, if the above-mentioned conveyance speed V and the angles alpha, beta of intersection are beforehand set, the flaw position (y) is given only by said time difference (t). The flaw position (x) in the conveyance direction is given as the position right under the detector when the flaw detection signal appears. |
