三针法测量螺纹中径的误差及补偿计算

The Error and Compensation Calculation of Measuring Screw Thread Middle Diameter with Three Pins Method

较精密螺纹的加工与测量常用三针法,而中径计算往往忽略了螺旋升角(λ)的影响,导致测量时发生误判。本文提供了测量误差的计算方法以及螺纹中径的正确计算公式。

Three pins method is widely used to process and measure higher precision screw thread,but spiral angle λ is always omitted in the middle diameter calculation,which leads to measuring error.A calculation method to measuring error and the correct calculation formula of middle diameter are introduced.