Patent ID: 6175813
Filing Date: 2001-01-16
Classification: G01B

Abstract:
An apparatus for measuring the geometric dimension of a part comprising:a rotational device for holding a part to be measured and for rotating said part about its center through a plurality of positions, said rotational device including a rotary table comprising a centering device having a centering disk for centering said part and a pin for defining a center location;a measuring device for measuring a radial distance from the center of the part to each of a plurality of surface points on said part as said part is rotated through angular measurement positions separated by an angle of rotation, said measuring device including a first measuring device for measuring an initial radial distance from the center of said part to an initial surface point on said part and a second measuring device for measuring radial displacement from said initial radial distance measurement to each measured point on said part, wherein said first measuring device comprises a linear slide device for measuring linear displacement from said initial surface point to said center of said part; anda controller for calculating a circumferential distance between successive measured points measured on said part as a function of the measured radial distance at each measured point and said angle of rotation, said controller further summing a plurality of said circumferential distances taken through a 360 degree rotation of said part to provide a circumference measurement of said part.