目前16S251是成为当今世界最强有力同步啮合的变速器.The 16 S 251 is now the most powerful synchromesh transmission in the world.齿合系数 --- 啮合的平均齿数.Contact ratio: the average number of teeth in contact.互相啮合的直齿圆柱齿轮,必须具有相同的径节.Meshing spur gears must...