It's a sort of "smart" wheel that contains most of the mechanical parts of the car-drive train, suspension, and braking.

这是种车的“智能”轮胎具备大部分汽车的机械部分功能——驱动系统、悬置系统、制动系统。

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The clock spring is operably coupled to another of the gears in the gear train, configured to store mechanical energy supplied by the motor, and configured to drive the control valve.

表簧可操作地联接到在齿轮系中的齿轮中的另一个上，构造成存储由电动机供给的机械能，及构造成驱动控制阀。

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And without any grand programme, Mr Smith is also cutting the number of basic car platforms (the chassis and drive-train mechanical bits that make the wheels go round) from 16 to eight, in line with best practice at firms such as Ford, Volkswagen and Toyota.

ECONOMIST: The quiet man