A Study on The Key Technology of The Online Measurement Device for Joint Internal Thread

摘要

This paper describes the design and realization of an online measurement device used for Joint Internal Thread. The online measurement device adopts the principle that the shaft section of two dimensional tooth profile of Joint Internal Thread was obtained with the passive contact method. A novel first derivative segmentation method based on the dynamic linear regression was used to classify and identify the two-dimensional tooth profile data. The basic and derived parameter of Joint Internal Thread was then quickly calculated. The tooth height of Joint Internal Thread was used as the traceable standard to calibrate the online measurement device. The comparison between field experiment data and manually measured data shows that the online measurement device is a rational design which works stably, shortens the measurement time largely, and improves the efficiency. The measured results satisfies the accuracy requirement.