METHOD FOR COMPUTING RADIUS OF GRINDING WHEEL OF GRINDER

PROBLEM TO BE SOLVED: To provide a method for computing the radius of a grinding wheel capable of measuring the radius of the grinding wheel at high precision without using a dedicated measuring device. SOLUTION: A center-to-center distance Rgpc between a rotation center P of the grinding wheel 18 and a center Op of a pin part 14a is recorded in a recording medium as addition of a temporary radius Rgc of the grinding wheel 18 and a target grinding radius Rpc of the pin part. An operation expression to determine distance between a rotation center O of a crankshaft 14 and the rotation center P of the grinding wheel, that is machining data X, is preliminarily recorded in the recording medium. Grinding work to the pin part 14a is conducted by numerical control in accordance with a grinding work program using this operation expression. In finish grinding, the diameter of the pin part is measured by a sizing device 29, and an actual radius Rpx is computed based on the diameter. The real radius Rpx of the pin part 14a is subtracted from the center-to-center distance Rgpc, thereby the real radius Rgx of the grinding wheel is computed.