Patent ID: 9470509
Filing Date: 2016-10-18
CPC Classification: G01B

Claim Text:
1. An inner diameter measuring device, comprising a measurement carriage traveled in straight direction, pipe holding frames disposed at front and rear positions with respect to advancing direction of said measurement carriage and for mounting a pipe to be measured, a measuring head supported at a forward end of a support extended in a direction parallel to advancing direction of said measurement carriage, a first laser distance measuring detector and a second laser distance measuring detector disposed in traveling distance of said measurement carriage and for performing distance measurement in two directions perpendicularly crossing to each other, wherein said pipe holding frames can adjust a supporting position of said pipe to be measured as mounted in horizontal direction and in vertical direction, said measuring head measures an inner diameter of said pipe to be measured on condition that said measuring head is inserted in said pipe to be measured, reference outer peripheral surfaces being formed at least at two parts at front and rear positions on said pipe to be measured, said first laser distance measuring detector and said second laser distance measuring detector measure distance with respect to each of the reference outer peripheral surfaces at said two parts, and the supporting position of said pipe to be measured is adjusted by said pipe holding frames so that results of measurement by said first laser distance measuring detector and said second laser distance measuring detector at said two parts become minimum values.