九、汪克尔发动机

Have you ever seen a Wankel engine（or a rotary engine）？It is so called，because it was first invented by a German inventor Felix Wankel.

The Wankel engine makes of a three-lobe rotor that rotates eccentrically in an oval chamber.The rotor is mounted on the crankshaft through internal and external gears.The Wankel engine does its four cycles，i.e.，intake，compression，power and exhaust just as the conventional piston engine.

The advantages of the Wankel engine are that the engine for a given specific power output is appreciably smaller in size and weight than the equivalent petrol engine.It contains no reciprocating parts so that no unbalanced inertia forces occur.It has no valves or valve gears and in all has appreciably fewer parts than the ordinary petrol engine and with modern high precision machining methods and advanced materials it is claimed to be cheaper，when mass produced，than the petrol engine.

【译文】

你曾看到过汪克尔发动机（或转子发动机）吗？之所以如此称呼，是因为它是由德国发明家费力克斯 · 汪克尔首先发明的。

汪克尔发动机利用一只三角转子在一个椭圆形的气缸内做偏心旋转来工作。转子通过内、外齿轮安装在曲轴上。就像传统的活塞式发动机那样，汪克尔发动机进行四冲程工作循环，即进气冲程、压缩冲程、做功冲程和排气冲程。

汪克尔发动机的优点在于：在相同比功率输出的条件下，该发动机要比其他汽油发动机质量轻、体积小。该发动机没有往复运动件，因此，没有不平衡的惯性力。汪克尔发动机没有气门和气门机构等。总之，汪克尔发动机的零件数明显地少于一般的汽油发动机。可以断言，采用现代高精度机械制造方法和先进的材料，在大批量生产时，汪克尔发动机将比一般汽油发动机的价格便宜。