为了研制高精度标准齿轮，以Y7125磨齿机为例分析了大平面砂轮磨削面锥形误差对齿轮螺旋线偏差的影响。建立了磨削的几何模型，推导出了影响量的数学表达式。理论分析结果显示，砂轮与齿面有效接触宽度对齿轮螺旋线形状偏差的影响不大，而随着被磨齿轮齿宽的加大，对齿轮螺旋线形状偏差的影响系数会显著增大；砂轮磨削面锥形误差使被磨齿轮螺旋线偏差曲线呈弧形，且弧度从齿根到齿顶逐渐增大。最后通过一实例进行了误差测量、磨齿实验与偏差分析。研究结果表明，控制大平面砂轮磨削面的锥形误差在2.7′以内可满足加工1级螺旋线精度齿轮的加工要求。

In order to develop ultra precision master gears, this paper takes the Y7125 grinder as an example to analyze the effect of the cone-shaped error of grinding face on the helix deviations.It establishes a geometric model and derives the numeric expression of the effect.The theoretical results show that the minimum effective bearing width has a little effect on the form deviation of gear helix.However, as the increase of gear width, the effect of the cone-shaped error on the form deviation of gear helix will significantly increase.Moreover, the cone-shaped error can make the curve of gear helix deviation to be an arc-shape and the crowns of arc vary from the dedendum to the addendum.Finally, the error measurement, gear-grinding experiment and deviation analysis are conducted by an example.The results show that the ultra-precision gear can achieve the quality of 1 helix deviation by controlling the cone-shaped error of grinding face of flat faced wheel under 2.7′.