fixed gear meaning in Chinese

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Its principle of work is as follows : when raw material entered into the crushing chamber , it is broken under the impacting of movable and fixed gear disks that are rotated in high speed and then becomes the needed raw material through screen
本机的工作原理是物料进入粉碎室在高速旋转的活动齿盘与固定齿盘受齿的冲击的作用下被粉碎，经筛网筛选后即成为所需的粉料。