基于高精度测量的内燃机缸盖结合面密封路径的密封性能分析

摘要

Based on the precise measurement data of combustion engine matched surfaces of cylinder block and head obtained from Shapix surface detective, sealing performance is evaluated.Firstly, a sealing path along the cylinder port on the cylinder head surface binding was determined, and coordinate values along the path were obtained.Secondly, Gaussian filter based on approximating spline was used to obtain the surface profile after fitting along the sealing path.Thirdly, based on Motif combined morphological filtering, the surface texture of gasket along the sealing path after assembly was achieved.Finally, the sealing performance of the sealing path was determined by calculating the void area between the gasket and cylinder head.The result shows:the use of Gaussian filter based on approximating spline not only gains similar surface profile as Gaussian filter but also restrains the end distortion;using surface profile measurements can not only evaluate engine`s cylinder head sealing performance but also determine the leaking location.%以Shapix表面侦测仪获取的发动机缸盖结合面表面轮廓的高精度测量数据为基础,对缸盖结合面的密封性能进行评价.首先在缸盖结合面上设定一条沿缸口的密封路径,并提取其表面轮廓的测量数据;再分别利用基于逼近样条的高斯滤波和基于Motif合并的形态学滤波拟合出了装配后密封路径上缸盖结合面的表面轮廓及垫片的轮廓;最后通过计算密封路径上的垫片表面轮廓与缸盖表面轮廓之间的空隙面积,评价该路径的密封性能.研究结果表明:利用基于逼近样条的高斯滤波法获取表面轮廓既能得到与高斯滤波法一致的表面轮廓,又能克服其边缘失真的问题;基于表面轮廓测量数据既可以对发动机缸盖上密封路径的密封性进行评价,又可以确定失效的位置.