center pinion

基本解释

Some cars have variable-ratio steering, which uses a rack-and-pinion gear set that has a different tooth pitch (number of teeth per inch) in the center than it has on the outside.
有些车的转向系角传动比是可变的，这种转向器采用齿轮齿条式，它在中间而不是外部，有不同的齿密度（每寸齿数）。
The hypoid gear is in common use today due mainly to the fact that the offset pinion allows the propeller shaft to be set below, (for cars) or above, (for commercial vehicles) the crown wheel center.
现在的主减速器普遍使用准双曲面圆锥齿轮，这主要是因为主动锥齿轮的偏移允许轿车上传动轴布置得比从动锥齿轮低一些，而商用车上又允许布置得比从动锥齿轮高一些。