例1一台五征牌三轮农用运输车,只能挂Ⅳ挡以下的低速挡而高挡挂不上,当副变速杆由慢挡变快挡时就自动脱挡,打开变速箱检查发现副变速轴最右边(往前进方向看)与快慢挡滑动齿轮相啮合的主动小齿轮严重磨损,与滑动齿轮相啮合的齿轮厚度磨损到不足2mm,有些齿已经完全折断,只剩齿根。造成该齿轮磨损原因,一是副变速小齿轮与滑移齿轮只有全齿宽的1/3相啮合,齿轮只有很小部分传递动力,长时间承受碰撞、冲击加速磨损。二是副变速轴右 Example 1 A Wu Zheng brand three-wheeled agricultural vehicles, can only be linked below the low gear of Ⅳ gear and the high gear can not hang up, when the auxiliary gear shift from the slow block to automatically block when the gear shift, open the gear box to find that The auxiliary pinion on the rightmost side of the auxiliary speed change shaft (seen in the forward direction) engages with the fast and slow slippery gears. The gear pinion meshing with the sliding gear wears to less than 2mm in thickness. Some of the teeth have been completely broken and only the tooth roots remain. Cause gear wear reasons, first, the deputy variable speed pinion and slip gear meshing only one-third of the entire tooth width, only a small part of the gear transmission of power, bear a long time to impact, accelerated wear and tear. The second is the right side of the gearbox