实验室常用的永磁体(如条形磁铁、蹄形磁铁、磁针等),由于使用或保管不当,以及使用年代较久,它的磁性会逐渐减弱甚至消失,严重影响教学实验效果。为此,须用充磁器对磁体进行充磁,加强或恢复它的磁性。以前我们按照有关材料制作的充磁器电路如图1所示。这种充磁器,充磁电流大,线 The permanent magnets (such as bar magnets, hoof magnets, magnetic needles, etc.) commonly used in laboratories, due to improper use or storage, as well as the use of older, its magnetic properties will gradually weaken or even disappear, seriously affecting the teaching experiment results. To do this, a magnet must be used to magnetize the magnet and reinforce or restore its magnetism. In the past, we developed a magnetizer circuit based on related materials as shown in Figure 1. This magnetizer has a large magnetizing current.