活令(螺母,如图1)是C620車床上的零件(1616車床、K96鏟齿車床等亦有类似零件),該零件从形状和尺寸上看,是車床上主要零件中最小最簡单的,但它的技术要求是主要零件中比較高的。要求:(1)梯形螺孔中心綫对φ35~(-0.017)中心綫不垂直度为0.02/100毫米。(2)梯形螺孔中心綫对φ35~(0.017)中心綫偏移差 The live parts (nuts, fig. 1) are part of the C620 lathe (similar to the 1616, K96, etc), which is the smallest and easiest of the major components on a lathe, in shape and size , But its technical requirements are higher in the main parts. Requirements: (1) trapezoidal screw hole center line φ35 ~ (-0.017) centerline non-perpendicularity of 0.02 / 100 mm. (2) Trapezoidal screw hole center line φ35 ~ (0.017) center line offset difference