铣床上铣削螺旋槽，一般的作法是在分度头的侧轴挂上齿轮，并与机床工作台丝杆上的齿轮相啮合以进行铣削加工。而这样的作法对于导程很小的工件就无法使用了。 我车间加工的拨叉齿轮槽（如图 １），为 １８０°左右槽，由于导程太小（１０ ｍｍ），无法使用侧轴分度法进行铣削 Milling machine milling spiral groove, the general approach is to hook the gear side of the indexing gear, and with the machine table screw gear meshing for milling. And such an approach can not be used with very small lead parts. I workshop gear fork gear slot (Figure 1), about 180 ° slot, due to the lead is too small (10 mm), can not be used side-axis indexing method of milling