Centering method and apparatus

摘要

A centering apparatus and method is provided which automatically measuring the radius or radius deviation of a large cylindrical bore, and shorten the time required for centering. The inspection apparatus is supported on a rise and fall base which is horizontally supported on a top portion of the large cylindrical bore in such a manner that it is allowed to vertically move in parallel with a fine wire which is hung perpendicularly from the center of the top portion. The inspection apparatus having a non-contact type two-dimensional position sensor for detecting the relative position of the fine wire to the cent-er of the inspection apparatus. The inspection apparatus is positioned at an arbitrary height. A pair of manipulator arms, which are in stalled on the inspection apparatus, which are substantially symmetrically balanced in gravity, are extended to a point immediately before an object to be measured, then a pair slider units mounted on the tip of one of the manipulator arms are extended until they come in contact with a object to be measured of the inner surface of the large cylindrical bore. Then the distance between the object to be measured and the reference position of the tip of one of the slider units is measured by a distance measuring device attached on the one of the slider units, or is measured by it after the vibration of the manipulator arms is isolated by contact members attached to the slider units, thereby the radius or radius deviation of the large cylindrical bore is measured.