PURPOSE: To improve magnetic characteristic at the surface of iron core by forming the area near the surface of iron core joined by the abutting method in the zig-zag step lap mode wherein the iron core layer which does not generate the cut-away part is considered as the center.
CONSTITUTION: The iron core blocks enclosed within the dotted line are abutted at the joining position 5 from the iron leg 1a to 1c and from the yoke 3a to 3c in the three stages step lap joint holding the step allowance. The step lap mode of three stages is arranged in zig-zag with the iron core not generating the cut- away part, namely the iron leg 1b - yoke 3b considered as the center. The step lap mode is formed at the area other than the surface of iron core. Thereby, rate of cut-away part is remarkably reduced at the surface of iron core. In other words, since the cut-away part is as much reduced at the surface of iron core where the iron core width is narrowed, magnetic saturation does not occur easily and magnetic characteristic is not deteriorated.
HAMADATE YOSHIO
OONO YASUNORI
