| 摘要 |
PURPOSE:To prevent magnetic balance from being lost where magnetization width varies by making the magnetization width small or large by specific width according to a magnetized part scanned earlier by a rotational angle sensor is large or small. CONSTITUTION:Magnetized parts R1-R8 are scanned by the rotational angle sensor 3. A column body 2 rotates counterclockwise, the magnetized part R2 is scanned earlier at positions where the magnetization width varies, i.e. between the magnetized parts R2 and R3, and the area R2 is larger than R3, so the magnetization width of the magnetized part R2 is made the specific width alphaless than magnetization width 2theta. Consequently, the magnetization widths of the magnetized parts R2 and R3 are (2theta-alpha) and (theta+alpha) respectively. Further, the magnetized part R6 is scanned earlier between the magnetized parts R6 and R7 and the area R6 is larger than R7, so the magnetization with of the magnetized part R6 is made the specific width alpha larger than magnetized width theta. Consequently, the magnetization widths of the magnetized parts R6 and R7 are (theta+alpha) and (2theta-alpha) respectively and the magnetic balance is prevented from being lost.
|
