磨齿机分度误差传递规律

为预测被加工齿轮的齿距加工精度,研究了Y7125型大平面砂轮磨齿机系统分度误差的传递规律。采用全闭环测量法对用作角度测量基准的正36面棱体进行了高精度标定;基于该正36面棱体和相对测量法在机提取机床36个等分点系统分度误差曲线;最后在磨齿机上进行精密磨齿实验,通过比较齿轮试件的齿距累积偏差与机床原始系统分度误差的差异,研究机床分度误差的传递规律,并通过实验得到磨齿机分度误差传递过程中的不确定度。实验结果表明:采用全闭环测量法标定正36面棱体的测量不确定度达到±0.05;磨齿机系统分度误差传递到被加工齿轮后,齿距累积总偏差由2.1m增大到2.6m,相对误差增加了24%;通过磨齿实验得到磨齿机分度误差传递过程中的不确定度为±0.6m。得到的机床分度误差传递规律可用于预测齿轮的齿距累积加工精度,为制定科学的磨齿工艺提供技术支持。

Indexing error transfer law of a gear grinding machine

To predict the pitch machining accuracy of a gear to be ground, the transfer law of the systematic indexing error of the gear-grinding machine (Y7125) with flat-faced grinding wheel was researched. The normal 36 prism for angle measurement datum was calibrated in high-precision by using the full closure measurement method, then the systematic indexing error curve with 36 equal points was extracted on-machine based on the normal 36 prism and the relative measurement method. Finally, the precision gear-grinding experiment was conducted on the gear-grinding machine. The indexing error transfer law of the machine was studied by comparing the difference between the cumulative pitch deviation of a gear specimen and the original systematic indexing error of the gear grinding machine, and the uncertainty during the error transfer process of the gear-grinding machine was obtained by experiments. Experimental results show that the measurement uncertainty of the full closure measurement method to calibrate the normal 36 prism reaches to 0.05″.The total cumulative pitch deviation varies from 2.1 μm to 2.6 μm and the relative error increases by 24% after the systematic indexing error of the gear grinding machine transfers to the gear to be ground. Moreover, the uncertainty during the error transfer process is ±0.6 μm. The transfer law of systematic indexing error of the gear-grinding machine from the experiments mentioned above can be used to predict the pitch machining accuracy of the gear to be ground and can provide technical supports for the development of the scientific gear-grinding process.