| 摘要 |
PROBLEM TO BE SOLVED: To provide a method and an apparatus for polarizing which exhibits no variation in polarization pitch, can be manufactured at a low price, and conveniently gives skew magnetization. SOLUTION: A method of magnetizing, wherein a current of which the polarity periodically alternates is applied to a magnetization head 12 located close to the perimeter of a tubular magnet 2 to alternately form the magnetic pole of different polarity at the perimeter of the magnet while the magnet 2 is rotated about the rotating axis Y, is given in such a manner that the magnet or the head 12 is relatively displaced along the rotating axis Y of the magnet to alternately and helically form the magnetic pole of different polarity at the perimeter of the magnet. In this method, the magnetic pole of different polarity is formed alternately and helically, and when the positions of a starting point (for example N pole) and an end point (S pole) formed at the perimeter of the magnet slightly overlap one another, an area where the end point (S pole) is formed is displaced above or below an area where the starting point (N pole), which allows the overlapped portion to be substantially decreased as compared with the method of magnetizing. |
