METHOD AND DEVICE FOR EXTERNAL MAGNETIZATION IN PERMANENT MAGNET ELECTRICAL ROTARY MACHINE

摘要

PURPOSE:To prevent uneven magnetization by magnetizing a permanent magnet through application of a capacitor power source onto a magnetizing yoke means applied onto the outer circumference of a yoke then magnetizing a stepped rotor through application of the capacitor power source onto the magnetizing yoke means. CONSTITUTION:A permanent magnet 3 is magnetized externally, with a rotor 4 being incorporated therein. At this time, a capacitor power source is applied on a magnetizing coil 8b. After first magnetization of the permanent magnet, the rotor 4 is rotated slightly through external force other than the capacitor power source and magnetized with the teeth 4a having low magnetic resistance being stepped to the section of the magnetized permanent magnet 3 having low flux density. When the displacement of rotary angle of the rotor 4 is set equal to half pitch of the rotor teeth 4a, the rotary angle is displaced to the pulse peak position of the capacitor power source upon second magnetization and magnetization at a section having low flux density can be augmented.