| 摘要 |
PURPOSE:To moderate influences due to unevenness of accuracy of size of parts or uneven quality in manufacturing process by interposing a non-magnetic spring between a non-magnetic collector supporting body and a circular magnetic pole piece which is the nearest to a collector portion. CONSTITUTION:A non-magnetic spring 10 is interposed between a circular magnetic pole piece 9 which is the nearest to a collector 7 and a non-magnetic collector supporting body 8. In this way, each one of circular permanent magnet 1 and a magnetic pole piece 2 are stuck to each other by interposing non-magnetic spring 10 due to the elasticity of the spring. And even in case that an actual size is not equal to the previously design the size due to uneven quality in manufacturing, fixed strength of the circular permanent magnet 1 is strong enough against mechanical impact. Thereby, periodic magnetic field focusing device of high reliance can be obtained. |
