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）。

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In this paper, the meshing theory of rack and pinion steering gear with variable ratio is studied systematically.

对汽车变速比齿轮齿条式转向器的啮合原理进行了系统研究。

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Another distinguishing feature is the speed-sensitive power steering with rack-and-pinion steering gear: the power assistance is implemented electrohydraulically rather than just hydraulically.

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