EDDY CURRENT FLAW DETECTOR

摘要

PURPOSE:To enable a highly accurate detection by winding insulator-coated conductors on a rectangular-like frame body with a square bottom as magnetic core passing the bottom and the top thereof to form two flat coils in such a manner as to cross each other at the right angle. CONSTITUTION:Flat coils 5 and 6 each have insulator-coated conductors wound on a rectangular parallelepiped 7 with a square bottom as magnetic core over the entire circumferential surface passing the bottom and the top surface thereof in such a manner as to cross each other at the right angle in the same number of turns. Both the flat coils 5 and 6 are almost the same in the shape. The flat coils 5' and 6' are just same in the shape and the numbers of turns as those of said flat coils 5 and 6. These two sets of the flat coils are so arranged with one following the other in the advancing direction A of work 1 to be measured that the flat coils 5 and 5' coincide with each other in the axis. This almost eliminates changes in the impedance due to any indent and minimizes effect from the difference in the shape thereby greatly facilitating discriminating of defects only.