Patent ID: 8473092

Claim:
A complete round working method in an numerical control (NC) machine tool for performing complete round working by contouring working with the NC machine tool that controls a motion of a main shaft by an NC working program, wherein the complete round working is performed by the steps of: performing NC operation according to a circular arc operation command before performing complete round working for a work in a state where a device for measuring a deviation from the complete round in a radial direction to the main shaft is attached to the main shaft; dividing a working route of the main shaft into a plurality of measurement points and setting the plurality of measurement points on the complete round by dividing the complete round at equal angles in a circumferential direction, wherein, for each measurement point, measuring a length from a center of the complete round to a point where a line drawn between the center of the complete round and each measurement point or an extended line thereof crosses the actual working route of the main shaft by using said device attached to the main shaft; comparing a measured value obtained from the measurement by said device with a radial length of the complete round to measure a deviation amount of the working route of the main shaft from the complete round at each of the measurement points; based on said deviation amount, calculating a correction value for correcting the working route of the main shaft at each of the measurement points, and incorporating this correction value into said NC working program; and controlling the motion of the main shaft according to said NC working program to perform the complete round working for the work, wherein said complete round is divided at equal angles of 360 0 /S in said circumferential direction where S represents number of samplings, and wherein said measuring of the deviation amount and said calculating of the correction value are repeated until a number of repetitions reaches S.