MAGNETIZING METHOD AND MAGNETIZING TOOL FOR MAGNETIC PLATE

摘要

PROBLEM TO BE SOLVED: To provide a permanent magnet plate with a greater (BH) max and an enhanced magnetic flux density distribution not causing degrading of an electromagnetic transduction efficiency of an electromagnetic transducer even when more or less position offset takes place in a diaphragm. SOLUTION: The magnetizing tool is provided with a lower tool 6A fixed to a base plate 7 and an upper tool 6B placed in a state of being placed on the lower tool 6A. Many parallel grooves 613 are formed on opposed faces of the lower tool 6A and the upper tool 6B in a way of traversing the faces, an electric conduction wire is alternately inserted through the grooves 613 in opposite directions so as to alternately form stripe magnetic poles with different polarity at positions of the one side and the other side corresponding to each other of a magnetic plate 9 clamped between the upper tool 6B and the lower tool 6A by a current supplied to each electric conduction wire 8 of the upper tool 6B and the lower tool 6A in the same direction while the magnetic plate 9 is inserted between the upper tool 6B and the lower tool 6A. COPYRIGHT: (C)2003,JPO