手把輸入旋轉運動，再轉動另一個小齒輪，由小齒輪轉動輪子。由於小齒輪中心位置沒有固定，因此如果轉動快，小齒輪本身就會移動，消耗了傳輸的動力，輪子就會轉慢。

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The pinion is rotated by the input from the handle, which drives the wheel. With high input angular velocity, the pinion will move about the handle and consume energy due to the axis of the pinion is not fixed, slowing the gear down