The design of millimeter-scale rotary engine(Wankel) was introduced, which is quite different from large-scale engine's parts design and manufacture.

介绍了毫米级微型转子发动机（汪克尔类型）的设计，其在各零部件的设计、加工上和大尺寸的转子发动机存在很大的不同；

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The Wankel engine in the Mazda RX-8 houses a rapidly spinning cam that is shaped to compress and combust fuel and air against the inside of an oval chamber.

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The last serious attempt, Felix Wankel's rotary engine, lingers on in Mazda's sports cars and is also used to power snowmobiles.

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