渐开线常用来作为齿轮齿廓曲线。虽然容易作出渐开线曲线,渐开线函数也易于求解,但要计算反渐开线函数则较困难。渐开线函数如下: ε=tgφ-φ=invφ反渐开线函数φ=inv~(-1)ε在齿轮设计中常常会碰到。若已知齿轮在某点的压力角φ,求invφ很容易。但若已知inv~(-1)ε时,从渐开线函数表中也可查出φ角值,但有时则需要经插值计算,这样得出的φ是近似值,精度不高。可用迭代法来求解反渐开线函数(见 Involute is often used as gear profile curve. Although it is easy to make an involute curve and an involute function is easy to solve, it is more difficult to calculate the inverse involute function. Involute functions are as follows: ε = tgφ-φ = invφ Anti-involute function φ = inv ~ (-1) ε is often encountered in gear design. If you know the pressure angle of the gear at a point φ, find invφ is easy. However, if inv ~ (-1) ε is known, the value of φ can also be found from the involute function table, but interpolation is sometimes required. The resulting φ is an approximate value and the accuracy is not high. Iteration method can be used to solve the inverse involute function (see