Battison Adrian D.`Ade & Company Inc. `Dupuis Ryan W.
摘要:
An apparatus and method for detection of imperfections by detecting changes in magnetic flux of a magnetized metal body includes a housing carrying first and second magnets for magnetizing the metal body that are located adjacent opposite ends of the housing and a conductor member intermediate the first and second magnets that has a forward end adjacent the metal body and extends outwardly from the metal body to an outer end of the conductor member. At this outer end there is provided a third magnet directing its magnetic field into the conductor member, and at the forward end of the conductor member there is provided a magnetic field sensor to detect changes in magnetic field in the metal body generated by the imperfections as the housing is moved in scanning movement along the metal body.