PURPOSE: To provide a titled sensor which can detect and decide the degree of stress concentration in a weld zone on the spot by detecting electrically the radius of curvature at the toe of weld as the projecting rate of a contactor projecting outward from the end face of a holder and comparing the electrical signal thereof with the electrical signal corresponding to the preset projecting rate of the contactor.
CONSTITUTION: A head 4 is pressed to a toe 1 of weld formed to a radius Rw of curvature. A contactor 6 does not project outward when Rw>Rs and therefore the amplified electrical signal (c) is zero. When Rw<Rs, the contactor 6 is pressed by a spring 8 and is projected until the contactor contacts with the toe 1 of weld. A core 8 is moved within a differential transformer 7 during this time and the electrical signal conforming to the projecting rate is fed to an amplifier 12. The amplifier 12 generates the signal (c) and a comparator 15 compares the signal (c) with the electrical signal (d) from a setter 14. When Rw<Rs, the projecting rate of the contactor 6 is larger than the permissible projecting rate rM and therefore an alarm is emitted to announce the defectiveness at the toe 1 of weld. When Rw>Rs, the projecting rate of the contactor 6 is smaller than the projecting rate rM and therefore an alarm is not emitted.
FUJI AKIO
OOTOMO AKIRA
MIYANARI YASUYOSHI
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