在车床上加工零件,它的轴向尺寸精度很难控制。这是因国产普通车床大拖板刻度环的刻度多数是每一小格lmm。我厂加工图1所示的零件,用原大拖板刻度环,15(?)的尺寸公差难以保证。现改动大拖板刻度环的传动齿抡,使原来1mm的刻度值改为0.2mm,保证了零件的寸尺要求。改动方法:做两个齿轮,见图2的(a)和 Machining parts on lathes makes it difficult to control the axial dimensional accuracy. This is due to domestic large lathe scale ring scale most of the small grid each lmm. I plant processing parts shown in Figure 1, with the original big scale scale ring, 15 (?) Dimensional tolerance is difficult to guarantee. Is to change the large carriage scale ring gear 齿, so that the original value of 1mm to 0.2mm, to ensure the size of the parts required. Change method: make two gears, see Figure 2 (a) and