Y742(5892A)高精度齿轮磨床磨制工件渐开线的准确度,取决于一可换的精密渐开线样板(见图1)。渐开线曲线在全长 200～300公厘上允差为0. 002公厘,渐开线表面与平面A之不平行度允差为0.004 公厘。为了达到该零件的精度要求,采取了如下两项措施: 1)对精磨凸轮样板所使用的机床── The accuracy of the Y742 (5892A) high-precision gear grinder grinding the workpiece involute depends on a changeable precision involute template (see Figure 1). Involute curve in the full length of 200 to 300 mm on the tolerance of 0. 002 mm, involute surface and plane A non-parallel tolerance of 0.004 mm. In order to meet the precision requirements of the part, the following two measures have been taken: 1) For the machine tool used for grinding cam model ──