对称螺纹作用中径的精确计算

The Exact Calculation of the Virtual Effective Diameter of Symmetrical Triangular Screw Thread

本文考虑了螺纹牙侧角偏差和螺距偏差的各种组合对作用中径的共同影响,设计了包容图位移法。运用此法分析和推导出以中径或以单一中径来计算作用中径的精确公式,并用实测数据验证了公式的正确性,又与现行简化公式作了比较。

This paper takes account of the combined effect on virtual effective diameter due to the several cases of flank angle deviation and pitch deviation in symmetrical triangular screw threads, and designs a displacing enveloping drawing method. By the use of the method, a set of exact formulae for calculating the virtual pitch diameter by the pitch diameter or by the single pitch diameter is deduced, verified by measured data. Comparison between the formulae and those approximate ones in general use is given.