螺纹中径参数“虚拟三针”测量方法(1)

Measuring Method of “Virtual Three Needle” for Parameters of Pitch Diameter of Thread(1)

在普通圆柱螺纹中径参数测量方法的讨论中,螺纹中径参数如何严格按照国家标准要求进测量,未取得明确共识。所有有关测量技术的教科书和参考书中的中径参数三针测量方法、计算公式,也未按定义给出一个确切的解释和公式推导。本文将在下面,从理论上论述这一问题。

In the discussion of measuring methods for pitch diameter parameters of common cylindrical threads, there is no clear consensus on how to strictly measure the parameters of pitch diameter of threads in accordance with the national standards. The three needle measurement method and calculation formula of for parameters of pitch diameter in all textbooks and reference books related to measurement technology have not given an exact explanation and formula derivation according to the definition. This paper will discuss this problem in theory as follows.