【摘要】 发动机缸盖排气门座锥面与气门配合精度是影响发动机功率的重要因素之一，因此必须严格控制缸盖排气门座锥面的深度尺寸。根据待测尺寸的结构特点进行了详细的技术分析，分析常规量具无法准确检测的原因，并从尺寸转换、球形定位及对比测量三个方面深入研究，设计出了一款定位准确、检测效率高的专用检具。详细描述了专用检具检测原理、结构设计、检测方法以及加工制造注意事项，同时对检具进行检测结果分析。结果表明，检具符合验收标准，满足使用要求；与现有检测技术比较，所设计的专用检具检测效率高，只需3s即可完成1件产品检测，准确率达到了99%;制造成本较低，具有较好的推广价值。更多还原

【Abstract】 The matching accuracy of cylinder head exhaust valve seat cone and valve is one of the important factors affecting engine power, so the depth of cylinder head exhaust valve seat cone must be strictly controlled.According to the structural characteristics of the size to be measured, a detailed technical analysis is carried out to analyze the reasons why the conventional measuring tools could not be accurately detected, and a special measuring tool with accurate positioning and high detection efficiency is designed from three aspects of dimension conversion, spherical positioning and comparative measurement.The testing principle, structure design, testing method and matters needing attention in design and manufacturing are described in detail.Meanwhile, the testing results are analyzed.The results show that the testing tools meet the acceptance standards and meet the requirements of use.Compared with the existing detection technology, the designed special fixture detection efficiency is high, only 3S can complete a product detection, the accuracy achieves 99%,the manufacturing cost is low, so the product has a good promotion value.更多还原