副传动轴 meaning in English

counter drive shaft
countershaft spindle

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。
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。