| 摘要 |
PROBLEM TO BE SOLVED: To correct an error of a main spindle head position caused by an error related to the C-axis and the B'-axis. SOLUTION: While turning angle of a B-axis member 8 about the B'-axis is fixed at a predetermined angle, a C-axis member 6 is turned about the C-axis, a main spindle tip position is measured every predetermined turning angle, and the axial vector of the C-axis member 6 is determined based on the measured values. While turning angle of the C-axis member 6 about the C-axis is fixed at a predetermined angle, a B-axis member 8 is turned about the B'- axis, the main spindle tip position is measured every predetermined turning angle, and the axial vector of the B-axis member 8 is determined based on the measured values. A position of the main spindle tip is determined in a turning state of the axial vectors about the axial line, and an error of a main spindle head position is corrected using, as the error of the main spindle head position, a difference between the position of the main spindle tip and a main spindle position having no error. |
