汽车、拖拉机在行驶中,变速杆从档位上自动回到空档位置上,这种现象称之为“跳档”。其主要原因有:①齿轮轮齿磨损过大,尤其是在长度上不均匀磨损;②由于轴承或衬套磨损,产生松旷,造成变速器轴线不同轴;③变速轨及叉产生变形或磨损严重;④变速叉轴的自锁机构失效(如变速轨定位槽磨损、自锁钢珠磨损、 Automobiles, tractors in driving, the gear lever from the gear automatically return to neutral position, a phenomenon called “jump file.” The main reasons are: ① gear tooth wear is too large, especially in the uneven wear on the length; ② due to bearing or bushing wear, resulting loose loose, resulting in transmission axis is not coaxial; ③ rail and fork deformation or wear Serious; ④ fork shaft self-locking mechanism failure (such as variable speed rail positioning groove wear, self-locking ball wear,