Thread pitch diameter measuring system

A gauge system for determining the thread pitch diameter of an internally or externally threaded article without the need for a physical standard for comparison purposes, and without the need for gauge styli specific to a single thread form or a single thread pitch, said system comprising:

• a) styli with means to mount the styli to a standard caliper, the styli having ball-ends for contact with the threads of a variety of threaded articles with a variety of thread pitches and forms;
• b) a processor containing information about the styli being used, and having means for inputting a description of a particular threaded article being measured as having internal or external threads, the thread form, and pitch therein, said processor receiving the reading from said caliper/styli system, said processor then calculating the following values:
• 1) the offset distance between the threaded article's pitch line and the center of the contacting stylus' ball end, based on said pitch, form and styli information;
• 2) the separation distance between the two styli ball end centers, based on said caliper reading and styli information;
• 3) the distance between the two styli ball end centers along a diametral line of the threaded article, based on said separation distance and pitch information;
• 4) the pitch diameter of the threaded article, based on said diametral distance and said offset distance;
• and
• c) a display connected to said processor for presenting said pitch diameter.