Abstract A flux source with four rotatable permanent magnet rods having access from two perpendicular directions through gaps exceeding the rod diameter can produce a continuously-variable flux density of up to ±300 mT at the centre when high-grade Nd-Fe-B magnets are used. The trade-off between field, access and torque in this mangle design is discussed. The maximum field, achievable when the magnets touch, is equal to the remanence of the Nd-Fe-B. The torque needed to rotate the rods scales as the square of the remanence, and it increases faster than the inverse square of the separation when the separation is comparable to the rod diameter. End effects reduce the torque significantly, but appropriate gearing is needed to ensure smooth operation. Modifications of the basic design can reduce or compensate the torque by using special end pieces, and improve access to fields > 1000 mT at small rod separation.

中文翻译：

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开放存取永磁可变磁通源中的扭矩

摘要 当使用高级 Nd-Fe-B 磁体时，具有四个可旋转永磁棒的磁通源可以从两个垂直方向穿过超过棒直径的间隙，在中心产生高达 ±300 mT 的连续可变磁通密度。用过的。讨论了这种热轧机设计中场、通路和扭矩之间的权衡。磁铁接触时可达到的最大磁场等于 Nd-Fe-B 的剩磁。旋转棒所需的扭矩与剩磁的平方成正比，当间距与棒直径相当时，它比间距的平方反比增加得更快。末端效应会显着降低扭矩，但需要适当的传动装置以确保平稳运行。基本设计的修改可以通过使用特殊的末端件来减少或补偿扭矩，