| 摘要 |
PROBLEM TO BE SOLVED: To reduce the wearout of the contact part of a friction load or an excitation core when moving a wire rope, to omit bulk demagnetization operation being required when terminating damage detection operation, and to minimize the influence of the traveling speed of the wire rope. SOLUTION: In a magnetic flaw-detecting device, when a wire rope 3 being arranged near the tip part of a main core at both edges of an E-shaped core being excited by an excitation and detection cores 1a and 1b at the center is relatively moved in the longitudinal direction, and the damage of the surface of the wire rope 3 is detected by electromotive force being excited by detection coils 2a and 2b being wound on the detection cores 1a and 1b, AC power is supplied to the excitation coils 2c and 2d, a damage detection signal|en1|being obtained by rectifying and amplifying the electromotive force ea and eb being excited by the detection coils 2a and 2b using a rectifying amplifier 4 is compared with high, middle, and low thresholds Th , Tm , and Tl using a comparator 5, and counter values Ch , Cm , and Cl of the damage detection signal|en1 exceeding the thresholds are outputted to a display 6 for displaying at each of display parts 6a, 6b, and 6c.
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