SPHERICITY MEASURING APPARATUS, SPHERICITY MEASURING APPARATUS FOR BALL END MILL AND METHOD FOR MEASURING SPHERICITY OF OBJECT TO BE MEASURED HAVING NOTCHED SPHERICAL PART

摘要

PURPOSE:To easily measure the sphericity of an object, whose spherical part is notched complicatedly, with high accuracy, by arranging a positioning turntable on a bed and further arranging a laser measuring device and a position detector on the turntable. CONSTITUTION:Positioning turntables 3, 8 are provided on a bed 1. The control motor 32 of the work head 2 of the turntable 3 controls not only the rotation of a ball end mill 4 being an object to be measured whose spherical part is partially notched but also the sliding of the head 2 in the axial direction thereof. The rotary shaft of the turntable 8 crosses the axial line of the head at a right angle. The laser measuring devices 6a, 6b on the turntable 8 are arranged so that the measuring ranges thereof are set on the plane containing the rotary shaft of the turntable 8 and the R-accuracy of the mill 4 is measured. When the place to be measured of the mill 4 crosses the plane forming the laser measuring ranges at a right angle and is positioned on the plane containing the axial line of the head 2, the presence of the mill 4 is sensed by the position detector 7 on the turntable 8 to perform positioning.