Wirbelstrom-Induktionssonde zur Feststellung von Rissen und Verfahren zur Prüfung von Metallblech auf Risse

摘要

A probe 1, 2 for detecting flaws in sheet metal 14, 15, 16 in the region of a fastener 11 piercing the metal sheet or sheets, comprises a coil 3 for including an eddy current in the region of the fastener under inspection and eddy current sensor coils 4A - 4D having axes parallel to but spaced around the axis of coil 3. When the axis of the coil 3 is aligned with the fastener, the sensor coil can be moved around the axis of the fastener in a plane parallel to the metal sheet or sheets. The guide means 2 has a central aperture 10 and friction feet 9 so that it can be located over a fastener before the probe is inserted into it. An electromagnetic shield 6, screens the spring coils 4 from coil 3 and screens 5, 12 reduce the effect of outside influences and the fastener respectively on the probe. <IMAGE>