The crankshaft, regarded as the "backbone" of the engine, serves to change the reciprocating motion of the piston into rotary motion and handles the entire power output.

曲轴，也叫做发动机的“脊柱”，其作用是将活塞的上下往复运动转换成为旋转运动，并且控制着整个的功率输出。

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