High-precision sphere size measuring device and sphere polishing device

A high-precision sphere size measuring device mounted on a sphere polishing device configured to process spheres, the high-precision sphere size measuring device comprising:

• a sphere size measuring unit configured to measure each diameter parameter of a standard sphere and an object sphere that is in a course of processing by the sphere polishing device, the diameter parameter being obtained by adding a certain fixed value to each diameter;
• a size difference calculation unit configured to obtain, as a size difference between the diameter of the object sphere and the diameter of the standard sphere, a difference between the diameter parameter of the object sphere and the diameter parameter of the standard sphere both measured by the sphere size measuring unit;
• and
• a determination unit configured to compare the size difference with a threshold value so as to determine whether or not the diameter of the object sphere reaches a target value,
• wherein the sphere size measuring unit includes a washing part configured to wash, with washing oil, the object sphere before the measurement, and
• wherein the sphere size measuring unit measures the object sphere and the standard sphere in the washing oil so as to measure the object sphere and the standard sphere under a same environment and to prevent measurement accuracy from being affected by expansion or contraction of the spheres.