METHOD AND DEVICE FOR INSPECTION OF CRANKSHAFT

摘要

[Problem] To provide an inspection method and the like for accurately detecting defects that partially occur in a crankshaft such as underfilling and denting by distinguishing the defects from bending and twisting over the entire length of the crankshaft. [Solution] The present invention includes a step of obtaining three-dimensional point group data over the entire length of a region to be measured of a crankshaft S by an optical three-dimensional shape measurement device 1; a step of dividing the obtained three-dimensional point group data into a plurality of subregions along a direction parallel to the rotational axis L of the crankshaft and generating three-dimensional point group data for each subregion; a step of subjecting the generated three-dimensional group data of each subregion to parallel displacement and rotational displacement to be superimposed on a surface shape model of the crankshaft such that the distance of the three-dimensional point group data of each subregion to the surface shape model of the crankshaft becomes a minimum; and a step of detecting partial defects such as underfilling of the crankshaft on the basis of the distance between the subregional three-dimensional point group data and the surface shape model after the superimposition.