平面三滚柱定心夹具主要结构参数的公差分析

Tolerance Analysis of Main Structure Parameters of Planar Three Roller Centering Fixture

针对使用带平面三滚柱自定心夹具的工件需自锁并能方便松开的要求,分析了夹具各结构参数的公差对工件内孔尺寸精度要求的影响程度,提出了滚柱直径和楔紧平面到心轴中心距的公差计算方法。得出如下结论:工件内孔尺寸必须满足一定的精度要求;内孔所需的精度等级不仅与滚柱和楔紧平面到心轴中心距离的制造精度有关,还与工件内径的大小有关,且内径尺寸越大,所需的精度等级越低,为带平面三滚柱自定心夹具设计提供参考。

According to locking and convenient release requirements of the workpiece with planar three roller centering fixture, the influence degree of the fixture structure parameters tolerance to the inner hole size precision of the workpiece was analyzed,the tol-erance calculation methods of the roller diameter and center distance of the wedge surface to the mandrel were put forward. The conclu-sions are：the size of the inner hole of the workpiece must satisfy a certain precision;the accuracy class of inner hole is related not only with the manufacturing precision of the roller and the center distance of the wedge surface to the mandrel,but also with the workpiece inner diameter,and the diameter is greater,the precision grade required is lower. The research provides reference for the plane three roller centering fixture design.