Generally speaking, hollow shaft type of small volume, but the amount of magnetic force (magnetic power) also stretch out shaft type than for small.

一般而言，空心轴式的体积较小，而所需磁化力(磁动力)亦比伸出轴式为小。

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Mitsubishi magnetic powder clutch and brake can be divided into stretch out shaft type and hollow shaft type two kinds.

三菱磁粉离合器及制动器可分为伸出轴式及空心轴式两种。

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The main shaft between the air compressor and the gas turbine in a jet aircraft engine is hollow to permit an internal speed reduction shaft with the minimum requirement of space and weight.

在喷气式飞机发动机内位于空气压缩和燃气涡轮之间的主轴是空心的，允许有一个需要最小空间和重量的内部减速轴。

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