n.对轴
Countershaft assembly uses tapered bearings to reduce end play and extend gear life. 中间轴组合使用锥形滚柱轴承以减少轴向间隙并延长齿轮使用寿命。
Hence, the countershaft and all its rigidly connected gears are in motion whenever the drive shaft revolves. 因此，当驱动轴旋转时，副传动轴及与其刚性连接的齿轮都处于运动中。
Gear A , at the end of the drive shaft, and gear B, on the countershaft, are in constant mesh. 齿轮A位于驱动轴的末端，齿轮B在副传动轴上，它们恒定啮合。
When none of the sliding gears is in mesh with its countershaft gear, the gears are said to be in “neutral. 如果没有变速齿轮组与副传动轴上的齿轮啮合，这时，就叫做空挡。
Practice indicated that applying this process can realize mass production of automotive countershaft. 结果表明，采用这种工艺实现了汽车中间轴毛坯的大批量生产。
